001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase;
019
020import static org.apache.hadoop.hbase.io.hfile.BlockType.MAGIC_LENGTH;
021
022import java.nio.ByteBuffer;
023import java.nio.charset.Charset;
024import java.util.Arrays;
025import java.util.Collections;
026import java.util.List;
027import java.util.UUID;
028import org.apache.commons.lang3.ArrayUtils;
029import org.apache.hadoop.hbase.util.Bytes;
030import org.apache.yetus.audience.InterfaceAudience;
031
032/**
033 * HConstants holds a bunch of HBase-related constants
034 */
035@InterfaceAudience.Public
036public final class HConstants {
037  // NOTICE!!!! Please do not add a constants here, unless they are referenced by a lot of classes.
038
039  // Bytes.UTF8_ENCODING should be updated if this changed
040  /** When we encode strings, we always specify UTF8 encoding */
041  public static final String UTF8_ENCODING = "UTF-8";
042
043  // Bytes.UTF8_CHARSET should be updated if this changed
044  /** When we encode strings, we always specify UTF8 encoding */
045  public static final Charset UTF8_CHARSET = Charset.forName(UTF8_ENCODING);
046  /**
047   * Default block size for an HFile.
048   */
049  public final static int DEFAULT_BLOCKSIZE = 64 * 1024;
050
051  /** Used as a magic return value while optimized index key feature enabled(HBASE-7845) */
052  public final static int INDEX_KEY_MAGIC = -2;
053
054  /*
055   * Name of directory that holds recovered edits written by the wal log splitting code, one per
056   * region
057   */
058  public static final String RECOVERED_EDITS_DIR = "recovered.edits";
059
060  /*
061   * Name of directory that holds recovered hfiles written by the wal log splitting code, one per
062   * region
063   */
064  public static final String RECOVERED_HFILES_DIR = "recovered.hfiles";
065
066  /**
067   * Date Tiered Compaction tmp dir prefix name if use storage policy
068   */
069  public static final String STORAGE_POLICY_PREFIX = "storage_policy_";
070
071  /**
072   * The first four bytes of Hadoop RPC connections
073   */
074  public static final byte[] RPC_HEADER = new byte[] { 'H', 'B', 'a', 's' };
075  public static final byte RPC_CURRENT_VERSION = 0;
076
077  // HFileBlock constants. TODO!!!! THESE DEFINES BELONG IN HFILEBLOCK, NOT UP HERE.
078  // Needed down in hbase-common though by encoders but these encoders should not be dealing
079  // in the internals of hfileblocks. Fix encapsulation.
080
081  /** The size data structures with minor version is 0 */
082  public static final int HFILEBLOCK_HEADER_SIZE_NO_CHECKSUM =
083    MAGIC_LENGTH + 2 * Bytes.SIZEOF_INT + Bytes.SIZEOF_LONG;
084  /**
085   * The size of a version 2 HFile block header, minor version 1. There is a 1 byte checksum type,
086   * followed by a 4 byte bytesPerChecksum followed by another 4 byte value to store
087   * sizeofDataOnDisk.
088   */
089  public static final int HFILEBLOCK_HEADER_SIZE =
090    HFILEBLOCK_HEADER_SIZE_NO_CHECKSUM + Bytes.SIZEOF_BYTE + 2 * Bytes.SIZEOF_INT;
091  /** Just an array of bytes of the right size. */
092  public static final byte[] HFILEBLOCK_DUMMY_HEADER = new byte[HFILEBLOCK_HEADER_SIZE];
093
094  // End HFileBlockConstants.
095
096  /**
097   * Status codes used for return values of bulk operations.
098   */
099  @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC)
100  public enum OperationStatusCode {
101    NOT_RUN,
102    SUCCESS,
103    BAD_FAMILY,
104    STORE_TOO_BUSY,
105    SANITY_CHECK_FAILURE,
106    FAILURE
107  }
108
109  /** long constant for zero */
110  public static final Long ZERO_L = Long.valueOf(0L);
111  public static final String NINES = "99999999999999";
112  public static final String ZEROES = "00000000000000";
113
114  // For migration
115
116  /** name of version file */
117  public static final String VERSION_FILE_NAME = "hbase.version";
118
119  /**
120   * Current version of file system. Version 4 supports only one kind of bloom filter. Version 5
121   * changes versions in catalog table regions. Version 6 enables blockcaching on catalog tables.
122   * Version 7 introduces hfile -- hbase 0.19 to 0.20.. Version 8 introduces namespace
123   */
124  // public static final String FILE_SYSTEM_VERSION = "6";
125  public static final String FILE_SYSTEM_VERSION = "8";
126
127  // Configuration parameters
128
129  // TODO: Is having HBase homed on port 60k OK?
130
131  /** Cluster is in distributed mode or not */
132  public static final String CLUSTER_DISTRIBUTED = "hbase.cluster.distributed";
133
134  /** Config for pluggable load balancers */
135  public static final String HBASE_MASTER_LOADBALANCER_CLASS = "hbase.master.loadbalancer.class";
136
137  /** Config for balancing the cluster by table */
138  public static final String HBASE_MASTER_LOADBALANCE_BYTABLE = "hbase.master.loadbalance.bytable";
139
140  /** Config for the max percent of regions in transition */
141  public static final String HBASE_MASTER_BALANCER_MAX_RIT_PERCENT =
142    "hbase.master.balancer.maxRitPercent";
143
144  /** Default value for the max percent of regions in transition */
145  public static final double DEFAULT_HBASE_MASTER_BALANCER_MAX_RIT_PERCENT = 1.0;
146
147  /** Config for the max balancing time */
148  public static final String HBASE_BALANCER_MAX_BALANCING = "hbase.balancer.max.balancing";
149
150  /** Config for the balancer period */
151  public static final String HBASE_BALANCER_PERIOD = "hbase.balancer.period";
152
153  /** Default value for the balancer period */
154  public static final int DEFAULT_HBASE_BALANCER_PERIOD = 300000;
155
156  /**
157   * Config key for enable/disable automatically separate child regions to different region servers
158   * in the procedure of split regions. One child will be kept to the server where parent region is
159   * on, and the other child will be assigned to a random server. See HBASE-25518.
160   */
161  public static final String HBASE_ENABLE_SEPARATE_CHILD_REGIONS =
162    "hbase.master.auto.separate.child.regions.after.split.enabled";
163
164  /**
165   * Default value for automatically separate child regions to different region servers (set to
166   * "false" to keep all child regions to the server where parent region is on)
167   */
168  public static final boolean DEFAULT_HBASE_ENABLE_SEPARATE_CHILD_REGIONS = false;
169
170  /** The name of the ensemble table */
171  public static final TableName ENSEMBLE_TABLE_NAME = TableName.valueOf("hbase:ensemble");
172
173  /** Config for pluggable region normalizer */
174  public static final String HBASE_MASTER_NORMALIZER_CLASS = "hbase.master.normalizer.class";
175
176  /** Cluster is standalone or pseudo-distributed */
177  public static final boolean CLUSTER_IS_LOCAL = false;
178
179  /** Default value for cluster distributed mode */
180  public static final boolean DEFAULT_CLUSTER_DISTRIBUTED = CLUSTER_IS_LOCAL;
181
182  /** default host address */
183  public static final String DEFAULT_HOST = "0.0.0.0";
184
185  /** Parameter name for port master listens on. */
186  public static final String MASTER_PORT = "hbase.master.port";
187
188  /** default port that the master listens on */
189  public static final int DEFAULT_MASTER_PORT = 16000;
190
191  /** default port for master web api */
192  public static final int DEFAULT_MASTER_INFOPORT = 16010;
193
194  /** Configuration key for master web API port */
195  public static final String MASTER_INFO_PORT = "hbase.master.info.port";
196
197  /** Configuration key for the list of master host:ports **/
198  public static final String MASTER_ADDRS_KEY = "hbase.masters";
199
200  /** Full class name of the Zookeeper based connection registry implementation */
201  public static final String ZK_CONNECTION_REGISTRY_CLASS =
202    "org.apache.hadoop.hbase.client.ZKConnectionRegistry";
203
204  /** Parameter name for the master type being backup (waits for primary to go inactive). */
205  public static final String MASTER_TYPE_BACKUP = "hbase.master.backup";
206
207  /**
208   * by default every master is a possible primary master unless the conf explicitly overrides it
209   */
210  public static final boolean DEFAULT_MASTER_TYPE_BACKUP = false;
211
212  /** Name of ZooKeeper quorum configuration parameter. */
213  public static final String ZOOKEEPER_QUORUM = "hbase.zookeeper.quorum";
214
215  /** Name of ZooKeeper quorum configuration parameter for client to locate meta. */
216  public static final String CLIENT_ZOOKEEPER_QUORUM = "hbase.client.zookeeper.quorum";
217
218  /** Client port of ZooKeeper for client to locate meta */
219  public static final String CLIENT_ZOOKEEPER_CLIENT_PORT =
220    "hbase.client.zookeeper.property.clientPort";
221
222  /** Indicate whether the client ZK are observer nodes of the server ZK */
223  public static final String CLIENT_ZOOKEEPER_OBSERVER_MODE =
224    "hbase.client.zookeeper.observer.mode";
225  /** Assuming client zk not in observer mode and master need to synchronize information */
226  public static final boolean DEFAULT_CLIENT_ZOOKEEPER_OBSERVER_MODE = false;
227
228  /** Common prefix of ZooKeeper configuration properties */
229  public static final String ZK_CFG_PROPERTY_PREFIX = "hbase.zookeeper.property.";
230
231  public static final int ZK_CFG_PROPERTY_PREFIX_LEN = ZK_CFG_PROPERTY_PREFIX.length();
232
233  /**
234   * The ZK client port key in the ZK properties map. The name reflects the fact that this is not an
235   * HBase configuration key.
236   */
237  public static final String CLIENT_PORT_STR = "clientPort";
238
239  /** Parameter name for the client port that the zookeeper listens on */
240  public static final String ZOOKEEPER_CLIENT_PORT = ZK_CFG_PROPERTY_PREFIX + CLIENT_PORT_STR;
241
242  /** Default client port that the zookeeper listens on */
243  public static final int DEFAULT_ZOOKEEPER_CLIENT_PORT = 2181;
244
245  /** Parameter name for the root dir in ZK for this cluster */
246  public static final String ZOOKEEPER_ZNODE_PARENT = "zookeeper.znode.parent";
247
248  public static final String DEFAULT_ZOOKEEPER_ZNODE_PARENT = "/hbase";
249
250  /**
251   * Parameter name for the limit on concurrent client-side zookeeper connections
252   */
253  public static final String ZOOKEEPER_MAX_CLIENT_CNXNS = ZK_CFG_PROPERTY_PREFIX + "maxClientCnxns";
254
255  /** Parameter name for the ZK data directory */
256  public static final String ZOOKEEPER_DATA_DIR = ZK_CFG_PROPERTY_PREFIX + "dataDir";
257
258  /** Parameter name for the ZK tick time */
259  public static final String ZOOKEEPER_TICK_TIME = ZK_CFG_PROPERTY_PREFIX + "tickTime";
260
261  /** Default limit on concurrent client-side zookeeper connections */
262  public static final int DEFAULT_ZOOKEEPER_MAX_CLIENT_CNXNS = 300;
263
264  /** Configuration key for ZooKeeper session timeout */
265  public static final String ZK_SESSION_TIMEOUT = "zookeeper.session.timeout";
266
267  /** Timeout for the ZK sync() call */
268  public static final String ZK_SYNC_BLOCKING_TIMEOUT_MS = "hbase.zookeeper.sync.timeout.millis";
269  // Choice of the default value is based on the following ZK recommendation (from docs). Keeping it
270  // lower lets the callers fail fast in case of any issues.
271  // "The clients view of the system is guaranteed to be up-to-date within a certain time bound.
272  // (On the order of tens of seconds.) Either system changes will be seen by a client within this
273  // bound, or the client will detect a service outage."
274  public static final long ZK_SYNC_BLOCKING_TIMEOUT_DEFAULT_MS = 30 * 1000;
275
276  /** Default value for ZooKeeper session timeout */
277  public static final int DEFAULT_ZK_SESSION_TIMEOUT = 90 * 1000;
278
279  /** Parameter name for port region server listens on. */
280  public static final String REGIONSERVER_PORT = "hbase.regionserver.port";
281
282  /** Default port region server listens on. */
283  public static final int DEFAULT_REGIONSERVER_PORT = 16020;
284
285  /** default port for region server web api */
286  public static final int DEFAULT_REGIONSERVER_INFOPORT = 16030;
287
288  /** A configuration key for regionserver info port */
289  public static final String REGIONSERVER_INFO_PORT = "hbase.regionserver.info.port";
290
291  /** A flag that enables automatic selection of regionserver info port */
292  public static final String REGIONSERVER_INFO_PORT_AUTO = REGIONSERVER_INFO_PORT + ".auto";
293
294  /** Parameter name for what region server implementation to use. */
295  public static final String REGION_SERVER_IMPL = "hbase.regionserver.impl";
296
297  /** Parameter name for what master implementation to use. */
298  public static final String MASTER_IMPL = "hbase.master.impl";
299
300  /** Parameter name for how often threads should wake up */
301  public static final String THREAD_WAKE_FREQUENCY = "hbase.server.thread.wakefrequency";
302
303  /** Default value for thread wake frequency */
304  public static final int DEFAULT_THREAD_WAKE_FREQUENCY = 10 * 1000;
305
306  /** Parameter name for how often we should try to write a version file, before failing */
307  public static final String VERSION_FILE_WRITE_ATTEMPTS = "hbase.server.versionfile.writeattempts";
308
309  /** Parameter name for how often we should try to write a version file, before failing */
310  public static final int DEFAULT_VERSION_FILE_WRITE_ATTEMPTS = 3;
311
312  /** Parameter name and default value for how often a region should perform a major compaction */
313  public static final String MAJOR_COMPACTION_PERIOD = "hbase.hregion.majorcompaction";
314  public static final long DEFAULT_MAJOR_COMPACTION_PERIOD = 1000 * 60 * 60 * 24 * 7; // 7 days
315
316  /**
317   * Parameter name and default value for major compaction jitter. Used as a multiplier applied to
318   * {@link HConstants#MAJOR_COMPACTION_PERIOD} to cause compaction to occur a given amount of time
319   * either side of {@link HConstants#MAJOR_COMPACTION_PERIOD}. Default to 0.5 so jitter has us fall
320   * evenly either side of when the compaction should run.
321   */
322  public static final String MAJOR_COMPACTION_JITTER = "hbase.hregion.majorcompaction.jitter";
323  public static final float DEFAULT_MAJOR_COMPACTION_JITTER = 0.50F;
324
325  /** Parameter name for the maximum batch of KVs to be used in flushes and compactions */
326  public static final String COMPACTION_KV_MAX = "hbase.hstore.compaction.kv.max";
327  public static final int COMPACTION_KV_MAX_DEFAULT = 10;
328
329  /** Parameter name for the scanner size limit to be used in compactions */
330  public static final String COMPACTION_SCANNER_SIZE_MAX =
331    "hbase.hstore.compaction.scanner.size.limit";
332  public static final long COMPACTION_SCANNER_SIZE_MAX_DEFAULT = 10 * 1024 * 1024L; // 10MB
333
334  /** Parameter name for HBase instance root directory */
335  public static final String HBASE_DIR = "hbase.rootdir";
336
337  /** Parameter name for HBase client IPC pool type */
338  public static final String HBASE_CLIENT_IPC_POOL_TYPE = "hbase.client.ipc.pool.type";
339
340  /** Parameter name for HBase client IPC pool size */
341  public static final String HBASE_CLIENT_IPC_POOL_SIZE = "hbase.client.ipc.pool.size";
342
343  /** Parameter name for HBase client operation timeout. */
344  public static final String HBASE_CLIENT_OPERATION_TIMEOUT = "hbase.client.operation.timeout";
345
346  /** Parameter name for HBase client meta operation timeout. */
347  public static final String HBASE_CLIENT_META_OPERATION_TIMEOUT =
348    "hbase.client.meta.operation.timeout";
349
350  /** Default HBase client operation timeout, which is tantamount to a blocking call */
351  public static final int DEFAULT_HBASE_CLIENT_OPERATION_TIMEOUT = 1200000;
352
353  /** Parameter name for HBase client meta replica scan call timeout. */
354  public static final String HBASE_CLIENT_META_REPLICA_SCAN_TIMEOUT =
355    "hbase.client.meta.replica.scan.timeout";
356
357  /** Default HBase client meta replica scan call timeout, 1 second */
358  public static final int HBASE_CLIENT_META_REPLICA_SCAN_TIMEOUT_DEFAULT = 1000000;
359
360  /** Used to construct the name of the log directory for a region server */
361  public static final String HREGION_LOGDIR_NAME = "WALs";
362
363  /** Used to construct the name of the splitlog directory for a region server */
364  public static final String SPLIT_LOGDIR_NAME = "splitWAL";
365
366  /** Like the previous, but for old logs that are about to be deleted */
367  public static final String HREGION_OLDLOGDIR_NAME = "oldWALs";
368
369  /** Staging dir used by bulk load */
370  public static final String BULKLOAD_STAGING_DIR_NAME = "staging";
371
372  public static final String CORRUPT_DIR_NAME = "corrupt";
373
374  /** Used by HBCK to sideline backup data */
375  public static final String HBCK_SIDELINEDIR_NAME = ".hbck";
376
377  /** Any artifacts left from migration can be moved here */
378  public static final String MIGRATION_NAME = ".migration";
379
380  /** Used to construct the name of the compaction directory during compaction */
381  public static final String HREGION_COMPACTIONDIR_NAME = "compaction.dir";
382
383  /** Conf key for the max file size after which we split the region */
384  public static final String HREGION_MAX_FILESIZE = "hbase.hregion.max.filesize";
385
386  /** Default maximum file size */
387  public static final long DEFAULT_MAX_FILE_SIZE = 10 * 1024 * 1024 * 1024L;
388
389  /** Conf key for if we should sum overall region files size when check to split */
390  public static final String OVERALL_HREGION_FILES = "hbase.hregion.split.overallfiles";
391
392  /** Default overall region files */
393  public static final boolean DEFAULT_OVERALL_HREGION_FILES = true;
394
395  /**
396   * Max size of single row for Get's or Scan's without in-row scanning flag set.
397   */
398  public static final String TABLE_MAX_ROWSIZE_KEY = "hbase.table.max.rowsize";
399
400  /**
401   * Default max row size (1 Gb).
402   */
403  public static final long TABLE_MAX_ROWSIZE_DEFAULT = 1024 * 1024 * 1024L;
404
405  /**
406   * The max number of threads used for opening and closing stores or store files in parallel
407   */
408  public static final String HSTORE_OPEN_AND_CLOSE_THREADS_MAX =
409    "hbase.hstore.open.and.close.threads.max";
410
411  /**
412   * The default number for the max number of threads used for opening and closing stores or store
413   * files in parallel
414   */
415  public static final int DEFAULT_HSTORE_OPEN_AND_CLOSE_THREADS_MAX = 1;
416
417  /**
418   * Block updates if memstore has hbase.hregion.memstore.block.multiplier times
419   * hbase.hregion.memstore.flush.size bytes. Useful preventing runaway memstore during spikes in
420   * update traffic.
421   */
422  public static final String HREGION_MEMSTORE_BLOCK_MULTIPLIER =
423    "hbase.hregion.memstore.block.multiplier";
424
425  /**
426   * Default value for hbase.hregion.memstore.block.multiplier
427   */
428  public static final int DEFAULT_HREGION_MEMSTORE_BLOCK_MULTIPLIER = 4;
429
430  /** Conf key for the memstore size at which we flush the memstore */
431  public static final String HREGION_MEMSTORE_FLUSH_SIZE = "hbase.hregion.memstore.flush.size";
432
433  public static final String HREGION_EDITS_REPLAY_SKIP_ERRORS =
434    "hbase.hregion.edits.replay.skip.errors";
435
436  public static final boolean DEFAULT_HREGION_EDITS_REPLAY_SKIP_ERRORS = false;
437
438  /** Maximum value length, enforced on KeyValue construction */
439  public static final int MAXIMUM_VALUE_LENGTH = Integer.MAX_VALUE - 1;
440
441  /** name of the file for unique cluster ID */
442  public static final String CLUSTER_ID_FILE_NAME = "hbase.id";
443
444  /** Default value for cluster ID */
445  public static final String CLUSTER_ID_DEFAULT = "default-cluster";
446
447  /** Parameter name for # days to keep MVCC values during a major compaction */
448  public static final String KEEP_SEQID_PERIOD = "hbase.hstore.compaction.keep.seqId.period";
449  /** At least to keep MVCC values in hfiles for 5 days */
450  public static final int MIN_KEEP_SEQID_PERIOD = 5;
451
452  // Always store the location of the root table's HRegion.
453  // This HRegion is never split.
454
455  // region name = table + startkey + regionid. This is the row key.
456  // each row in the root and meta tables describes exactly 1 region
457  // Do we ever need to know all the information that we are storing?
458
459  // Note that the name of the root table starts with "-" and the name of the
460  // meta table starts with "." Why? it's a trick. It turns out that when we
461  // store region names in memory, we use a SortedMap. Since "-" sorts before
462  // "." (and since no other table name can start with either of these
463  // characters, the root region will always be the first entry in such a Map,
464  // followed by all the meta regions (which will be ordered by their starting
465  // row key as well), followed by all user tables. So when the Master is
466  // choosing regions to assign, it will always choose the root region first,
467  // followed by the meta regions, followed by user regions. Since the root
468  // and meta regions always need to be on-line, this ensures that they will
469  // be the first to be reassigned if the server(s) they are being served by
470  // should go down.
471
472  public static final String BASE_NAMESPACE_DIR = "data";
473
474  /** delimiter used between portions of a region name */
475  public static final int META_ROW_DELIMITER = ',';
476
477  /** The catalog family as a string */
478  public static final String CATALOG_FAMILY_STR = "info";
479
480  /** The catalog family */
481  public static final byte[] CATALOG_FAMILY = Bytes.toBytes(CATALOG_FAMILY_STR);
482
483  /** The RegionInfo qualifier as a string */
484  public static final String REGIONINFO_QUALIFIER_STR = "regioninfo";
485
486  /** The regioninfo column qualifier */
487  public static final byte[] REGIONINFO_QUALIFIER = Bytes.toBytes(REGIONINFO_QUALIFIER_STR);
488
489  /** The server column qualifier */
490  public static final String SERVER_QUALIFIER_STR = "server";
491  /** The server column qualifier */
492  public static final byte[] SERVER_QUALIFIER = Bytes.toBytes(SERVER_QUALIFIER_STR);
493
494  /** The startcode column qualifier */
495  public static final String STARTCODE_QUALIFIER_STR = "serverstartcode";
496  /** The startcode column qualifier */
497  public static final byte[] STARTCODE_QUALIFIER = Bytes.toBytes(STARTCODE_QUALIFIER_STR);
498
499  /** The open seqnum column qualifier */
500  public static final String SEQNUM_QUALIFIER_STR = "seqnumDuringOpen";
501  /** The open seqnum column qualifier */
502  public static final byte[] SEQNUM_QUALIFIER = Bytes.toBytes(SEQNUM_QUALIFIER_STR);
503
504  /** The state column qualifier */
505  public static final String STATE_QUALIFIER_STR = "state";
506
507  public static final byte[] STATE_QUALIFIER = Bytes.toBytes(STATE_QUALIFIER_STR);
508
509  /**
510   * The serverName column qualifier. Its the server where the region is transitioning on, while
511   * column server is the server where the region is opened on. They are the same when the region is
512   * in state OPEN.
513   */
514  public static final String SERVERNAME_QUALIFIER_STR = "sn";
515
516  public static final byte[] SERVERNAME_QUALIFIER = Bytes.toBytes(SERVERNAME_QUALIFIER_STR);
517
518  /** The lower-half split region column qualifier string. */
519  public static final String SPLITA_QUALIFIER_STR = "splitA";
520  /** The lower-half split region column qualifier */
521  public static final byte[] SPLITA_QUALIFIER = Bytes.toBytes(SPLITA_QUALIFIER_STR);
522
523  /** The upper-half split region column qualifier String. */
524  public static final String SPLITB_QUALIFIER_STR = "splitB";
525  /** The upper-half split region column qualifier */
526  public static final byte[] SPLITB_QUALIFIER = Bytes.toBytes(SPLITB_QUALIFIER_STR);
527
528  /**
529   * Merge qualifier prefix. We used to only allow two regions merge; mergeA and mergeB. Now we
530   * allow many to merge. Each region to merge will be referenced in a column whose qualifier starts
531   * with this define.
532   */
533  public static final String MERGE_QUALIFIER_PREFIX_STR = "merge";
534  public static final byte[] MERGE_QUALIFIER_PREFIX = Bytes.toBytes(MERGE_QUALIFIER_PREFIX_STR);
535
536  /**
537   * The lower-half merge region column qualifier
538   * @deprecated Since 2.3.0 and 2.2.1. Not used anymore. Instead we look for the
539   *             {@link #MERGE_QUALIFIER_PREFIX_STR} prefix.
540   */
541  @Deprecated
542  public static final byte[] MERGEA_QUALIFIER = Bytes.toBytes(MERGE_QUALIFIER_PREFIX_STR + "A");
543
544  /**
545   * The upper-half merge region column qualifier
546   * @deprecated Since 2.3.0 and 2.2.1. Not used anymore. Instead we look for the
547   *             {@link #MERGE_QUALIFIER_PREFIX_STR} prefix.
548   */
549  @Deprecated
550  public static final byte[] MERGEB_QUALIFIER = Bytes.toBytes(MERGE_QUALIFIER_PREFIX_STR + "B");
551
552  /** The catalog family as a string */
553  public static final String TABLE_FAMILY_STR = "table";
554
555  /** The catalog family */
556  public static final byte[] TABLE_FAMILY = Bytes.toBytes(TABLE_FAMILY_STR);
557
558  /** The serialized table state qualifier */
559  public static final byte[] TABLE_STATE_QUALIFIER = Bytes.toBytes("state");
560
561  /** The replication barrier family as a string */
562  public static final String REPLICATION_BARRIER_FAMILY_STR = "rep_barrier";
563
564  /** The replication barrier family */
565  public static final byte[] REPLICATION_BARRIER_FAMILY =
566    Bytes.toBytes(REPLICATION_BARRIER_FAMILY_STR);
567
568  /** The namespace family as a string */
569  public static final String NAMESPACE_FAMILY_STR = "ns";
570
571  /** The namespace family */
572  public static final byte[] NAMESPACE_FAMILY = Bytes.toBytes(NAMESPACE_FAMILY_STR);
573
574  public static final byte[] NAMESPACE_COL_DESC_QUALIFIER = Bytes.toBytes("d");
575  /**
576   * The meta table version column qualifier. We keep current version of the meta table in this
577   * column in <code>-ROOT-</code> table: i.e. in the 'info:v' column.
578   */
579  public static final byte[] META_VERSION_QUALIFIER = Bytes.toBytes("v");
580
581  /** The family str as a key in map */
582  public static final String FAMILY_KEY_STR = "family";
583
584  /**
585   * The current version of the meta table. - pre-hbase 0.92. There is no META_VERSION column in the
586   * root table in this case. The meta has HTableDescriptor serialized into the HRegionInfo; -
587   * version 0 is 0.92 and 0.94. Meta data has serialized HRegionInfo's using Writable
588   * serialization, and HRegionInfo's does not contain HTableDescriptors. - version 1 for 0.96+
589   * keeps HRegionInfo data structures, but changes the byte[] serialization from Writables to
590   * Protobuf. See HRegionInfo.VERSION
591   */
592  public static final short META_VERSION = 1;
593
594  // Other constants
595
596  /**
597   * An empty byte array instance.
598   */
599  public static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
600
601  /**
602   * An empty string instance.
603   */
604  public static final String EMPTY_STRING = "";
605
606  public static final ByteBuffer EMPTY_BYTE_BUFFER = ByteBuffer.wrap(EMPTY_BYTE_ARRAY);
607
608  /**
609   * Used by scanners, etc when they want to start at the beginning of a region
610   */
611  public static final byte[] EMPTY_START_ROW = EMPTY_BYTE_ARRAY;
612
613  /**
614   * Last row in a table.
615   */
616  public static final byte[] EMPTY_END_ROW = EMPTY_BYTE_ARRAY;
617
618  /**
619   * Used by scanners and others when they're trying to detect the end of a table
620   */
621  public static final byte[] LAST_ROW = EMPTY_BYTE_ARRAY;
622
623  /**
624   * Max length a row can have because of the limitation in TFile.
625   */
626  public static final int MAX_ROW_LENGTH = Short.MAX_VALUE;
627
628  /**
629   * Timestamp to use when we want to refer to the latest cell. On client side, this is the
630   * timestamp set by default when no timestamp is specified, to refer to the latest. On server
631   * side, this acts as a notation. (1) For a cell of Put, which has this notation, its timestamp
632   * will be replaced with server's current time. (2) For a cell of Delete, which has this notation,
633   * A. If the cell is of {@link KeyValue.Type#Delete}, HBase issues a Get operation firstly. a.
634   * When the count of cell it gets is less than the count of cell to delete, the timestamp of
635   * Delete cell will be replaced with server's current time. b. When the count of cell it gets is
636   * equal to the count of cell to delete, the timestamp of Delete cell will be replaced with the
637   * latest timestamp of cell it gets. (c. It is invalid and an exception will be thrown, if the
638   * count of cell it gets is greater than the count of cell to delete, as the max version of Get is
639   * set to the count of cell to delete.) B. If the cell is of other Delete types, like
640   * {@link KeyValue.Type#DeleteFamilyVersion}, {@link KeyValue.Type#DeleteColumn}, or
641   * {@link KeyValue.Type#DeleteFamily}, the timestamp of Delete cell will be replaced with server's
642   * current time. So that is why it is named as "latest" but assigned as the max value of Long.
643   */
644  public static final long LATEST_TIMESTAMP = Long.MAX_VALUE;
645
646  /**
647   * LATEST_TIMESTAMP in bytes form
648   */
649  public static final byte[] LATEST_TIMESTAMP_BYTES = {
650    // big-endian
651    (byte) (LATEST_TIMESTAMP >>> 56), (byte) (LATEST_TIMESTAMP >>> 48),
652    (byte) (LATEST_TIMESTAMP >>> 40), (byte) (LATEST_TIMESTAMP >>> 32),
653    (byte) (LATEST_TIMESTAMP >>> 24), (byte) (LATEST_TIMESTAMP >>> 16),
654    (byte) (LATEST_TIMESTAMP >>> 8), (byte) LATEST_TIMESTAMP, };
655
656  /**
657   * Define for 'return-all-versions'.
658   */
659  public static final int ALL_VERSIONS = Integer.MAX_VALUE;
660
661  /**
662   * Unlimited time-to-live.
663   */
664  // public static final int FOREVER = -1;
665  public static final int FOREVER = Integer.MAX_VALUE;
666
667  /**
668   * Seconds in a day, hour and minute
669   */
670  public static final int DAY_IN_SECONDS = 24 * 60 * 60;
671  public static final int HOUR_IN_SECONDS = 60 * 60;
672  public static final int MINUTE_IN_SECONDS = 60;
673
674  /**
675   * KB, MB, GB, TB equivalent to how many bytes
676   */
677  public static final long KB_IN_BYTES = 1024;
678  public static final long MB_IN_BYTES = 1024 * KB_IN_BYTES;
679  public static final long GB_IN_BYTES = 1024 * MB_IN_BYTES;
680  public static final long TB_IN_BYTES = 1024 * GB_IN_BYTES;
681
682  // TODO: although the following are referenced widely to format strings for
683  // the shell. They really aren't a part of the public API. It would be
684  // nice if we could put them somewhere where they did not need to be
685  // public. They could have package visibility
686  public static final String NAME = "NAME";
687  public static final String VERSIONS = "VERSIONS";
688  public static final String IN_MEMORY = "IN_MEMORY";
689  public static final String METADATA = "METADATA";
690  public static final String CONFIGURATION = "CONFIGURATION";
691
692  /**
693   * Retrying we multiply hbase.client.pause setting by what we have in this array until we run out
694   * of array items. Retries beyond this use the last number in the array. So, for example, if
695   * hbase.client.pause is 1 second, and maximum retries count hbase.client.retries.number is 10, we
696   * will retry at the following intervals: 1, 2, 3, 5, 10, 20, 40, 100, 100, 100. With 100ms, a
697   * back-off of 200 means 20s
698   */
699  public static final int[] RETRY_BACKOFF =
700    { 1, 2, 3, 5, 10, 20, 40, 100, 100, 100, 100, 200, 200 };
701
702  public static final String REGION_IMPL = "hbase.hregion.impl";
703
704  /**
705   * Scope tag for locally scoped data. This data will not be replicated.
706   */
707  public static final int REPLICATION_SCOPE_LOCAL = 0;
708
709  /**
710   * Scope tag for globally scoped data. This data will be replicated to all peers.
711   */
712  public static final int REPLICATION_SCOPE_GLOBAL = 1;
713
714  /**
715   * Default cluster ID, cannot be used to identify a cluster so a key with this value means it
716   * wasn't meant for replication.
717   */
718  public static final UUID DEFAULT_CLUSTER_ID = new UUID(0L, 0L);
719
720  /**
721   * Parameter name for maximum number of bytes returned when calling a scanner's next method.
722   * Controlled by the client.
723   */
724  public static final String HBASE_CLIENT_SCANNER_MAX_RESULT_SIZE_KEY =
725    "hbase.client.scanner.max.result.size";
726
727  /**
728   * Parameter name for maximum number of bytes returned when calling a scanner's next method.
729   * Controlled by the server.
730   */
731  public static final String HBASE_SERVER_SCANNER_MAX_RESULT_SIZE_KEY =
732    "hbase.server.scanner.max.result.size";
733
734  /**
735   * Maximum number of bytes returned when calling a scanner's next method. Note that when a single
736   * row is larger than this limit the row is still returned completely. The default value is 2MB.
737   */
738  public static final long DEFAULT_HBASE_CLIENT_SCANNER_MAX_RESULT_SIZE = 2 * 1024 * 1024;
739
740  /**
741   * Maximum number of bytes returned when calling a scanner's next method. Note that when a single
742   * row is larger than this limit the row is still returned completely. Safety setting to protect
743   * the region server. The default value is 100MB. (a client would rarely request larger chunks on
744   * purpose)
745   */
746  public static final long DEFAULT_HBASE_SERVER_SCANNER_MAX_RESULT_SIZE = 100 * 1024 * 1024;
747
748  /**
749   * Parameter name for client pause value, used mostly as value to wait before running a retry of a
750   * failed get, region lookup, etc.
751   */
752  public static final String HBASE_CLIENT_PAUSE = "hbase.client.pause";
753
754  /**
755   * Default value of {@link #HBASE_CLIENT_PAUSE}.
756   */
757  public static final long DEFAULT_HBASE_CLIENT_PAUSE = 100;
758
759  /**
760   * Parameter name for client pause value for special case such as call queue too big, etc.
761   * @deprecated Since 2.5.0, will be removed in 4.0.0. Please use
762   *             hbase.client.pause.server.overloaded instead.
763   */
764  @Deprecated
765  public static final String HBASE_CLIENT_PAUSE_FOR_CQTBE = "hbase.client.pause.cqtbe";
766
767  /**
768   * The maximum number of concurrent connections the client will maintain.
769   */
770  public static final String HBASE_CLIENT_MAX_TOTAL_TASKS = "hbase.client.max.total.tasks";
771
772  /**
773   * Default value of {@link #HBASE_CLIENT_MAX_TOTAL_TASKS}.
774   */
775  public static final int DEFAULT_HBASE_CLIENT_MAX_TOTAL_TASKS = 100;
776
777  /**
778   * The maximum number of concurrent connections the client will maintain to a single RegionServer.
779   */
780  public static final String HBASE_CLIENT_MAX_PERSERVER_TASKS = "hbase.client.max.perserver.tasks";
781
782  /**
783   * Default value of {@link #HBASE_CLIENT_MAX_PERSERVER_TASKS}.
784   */
785  public static final int DEFAULT_HBASE_CLIENT_MAX_PERSERVER_TASKS = 2;
786
787  /**
788   * The maximum number of concurrent connections the client will maintain to a single Region.
789   */
790  public static final String HBASE_CLIENT_MAX_PERREGION_TASKS = "hbase.client.max.perregion.tasks";
791
792  /**
793   * Default value of {@link #HBASE_CLIENT_MAX_PERREGION_TASKS}.
794   */
795  public static final int DEFAULT_HBASE_CLIENT_MAX_PERREGION_TASKS = 1;
796
797  /**
798   * The maximum number of concurrent pending RPC requests for one server in process level.
799   */
800  public static final String HBASE_CLIENT_PERSERVER_REQUESTS_THRESHOLD =
801    "hbase.client.perserver.requests.threshold";
802
803  /**
804   * Default value of {@link #HBASE_CLIENT_PERSERVER_REQUESTS_THRESHOLD}.
805   */
806  public static final int DEFAULT_HBASE_CLIENT_PERSERVER_REQUESTS_THRESHOLD = Integer.MAX_VALUE;
807
808  /**
809   * Parameter name for server pause value, used mostly as value to wait before running a retry of a
810   * failed operation.
811   */
812  public static final String HBASE_SERVER_PAUSE = "hbase.server.pause";
813
814  /**
815   * Default value of {@link #HBASE_SERVER_PAUSE}.
816   */
817  public static final int DEFAULT_HBASE_SERVER_PAUSE = 1000;
818
819  /**
820   * Parameter name for maximum retries, used as maximum for all retryable operations such as
821   * fetching of the root region from root region server, getting a cell's value, starting a row
822   * update, etc.
823   */
824  public static final String HBASE_CLIENT_RETRIES_NUMBER = "hbase.client.retries.number";
825
826  /**
827   * Default value of {@link #HBASE_CLIENT_RETRIES_NUMBER}.
828   */
829  public static final int DEFAULT_HBASE_CLIENT_RETRIES_NUMBER = 15;
830
831  public static final String HBASE_CLIENT_SERVERSIDE_RETRIES_MULTIPLIER =
832    "hbase.client.serverside.retries.multiplier";
833
834  public static final int DEFAULT_HBASE_CLIENT_SERVERSIDE_RETRIES_MULTIPLIER = 3;
835
836  /**
837   * Parameter name to set the default scanner caching for all clients.
838   */
839  public static final String HBASE_CLIENT_SCANNER_CACHING = "hbase.client.scanner.caching";
840
841  /**
842   * Default value for {@link #HBASE_CLIENT_SCANNER_CACHING}
843   */
844  public static final int DEFAULT_HBASE_CLIENT_SCANNER_CACHING = Integer.MAX_VALUE;
845
846  /**
847   * Parameter name for number of rows that will be fetched when calling next on a scanner if it is
848   * not served from memory. Higher caching values will enable faster scanners but will eat up more
849   * memory and some calls of next may take longer and longer times when the cache is empty.
850   */
851  public static final String HBASE_META_SCANNER_CACHING = "hbase.meta.scanner.caching";
852
853  /**
854   * Default value of {@link #HBASE_META_SCANNER_CACHING}.
855   */
856  public static final int DEFAULT_HBASE_META_SCANNER_CACHING = 100;
857
858  /**
859   * Parameter name for number of versions, kept by meta table.
860   */
861  public static final String HBASE_META_VERSIONS = "hbase.meta.versions";
862
863  /**
864   * Default value of {@link #HBASE_META_VERSIONS}.
865   */
866  public static final int DEFAULT_HBASE_META_VERSIONS = 3;
867
868  /**
869   * Parameter name for number of versions, kept by meta table.
870   */
871  public static final String HBASE_META_BLOCK_SIZE = "hbase.meta.blocksize";
872
873  /**
874   * Default value of {@link #HBASE_META_BLOCK_SIZE}.
875   */
876  public static final int DEFAULT_HBASE_META_BLOCK_SIZE = 8 * 1024;
877
878  /**
879   * Parameter name for unique identifier for this {@link org.apache.hadoop.conf.Configuration}
880   * instance. If there are two or more {@link org.apache.hadoop.conf.Configuration} instances that,
881   * for all intents and purposes, are the same except for their instance ids, then they will not be
882   * able to share the same org.apache.hadoop.hbase.client.HConnection instance. On the other hand,
883   * even if the instance ids are the same, it could result in non-shared
884   * org.apache.hadoop.hbase.client.HConnection instances if some of the other connection parameters
885   * differ.
886   */
887  public static final String HBASE_CLIENT_INSTANCE_ID = "hbase.client.instance.id";
888
889  /**
890   * The client scanner timeout period in milliseconds.
891   */
892  public static final String HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD =
893    "hbase.client.scanner.timeout.period";
894
895  /**
896   * Default value of {@link #HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD}.
897   */
898  public static final int DEFAULT_HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD = 60000;
899
900  /**
901   * timeout for each RPC
902   */
903  public static final String HBASE_RPC_TIMEOUT_KEY = "hbase.rpc.timeout";
904
905  /**
906   * timeout for each read RPC
907   */
908  public static final String HBASE_RPC_READ_TIMEOUT_KEY = "hbase.rpc.read.timeout";
909
910  /**
911   * timeout for each write RPC
912   */
913  public static final String HBASE_RPC_WRITE_TIMEOUT_KEY = "hbase.rpc.write.timeout";
914
915  /**
916   * Default value of {@link #HBASE_RPC_TIMEOUT_KEY}
917   */
918  public static final int DEFAULT_HBASE_RPC_TIMEOUT = 60000;
919
920  /**
921   * timeout for short operation RPC
922   */
923  public static final String HBASE_RPC_SHORTOPERATION_TIMEOUT_KEY =
924    "hbase.rpc.shortoperation.timeout";
925
926  /**
927   * Default value of {@link #HBASE_RPC_SHORTOPERATION_TIMEOUT_KEY}
928   */
929  public static final int DEFAULT_HBASE_RPC_SHORTOPERATION_TIMEOUT = 10000;
930
931  /**
932   * Retry pause time for short operation RPC
933   */
934  public static final String HBASE_RPC_SHORTOPERATION_RETRY_PAUSE_TIME =
935    "hbase.rpc.shortoperation.retry.pause.time";
936
937  /**
938   * Default value of {@link #HBASE_RPC_SHORTOPERATION_RETRY_PAUSE_TIME}
939   */
940  public static final long DEFAULT_HBASE_RPC_SHORTOPERATION_RETRY_PAUSE_TIME = 1000;
941
942  /**
943   * Value indicating the server name was saved with no sequence number.
944   */
945  public static final long NO_SEQNUM = -1;
946
947  /**
948   * Registry implementation to be used on the client side.
949   */
950  public static final String CLIENT_CONNECTION_REGISTRY_IMPL_CONF_KEY =
951    "hbase.client.registry.impl";
952
953  /*
954   * cluster replication constants.
955   */
956  public static final String REPLICATION_SOURCE_SERVICE_CLASSNAME =
957    "hbase.replication.source.service";
958  public static final String REPLICATION_SERVICE_CLASSNAME_DEFAULT =
959    "org.apache.hadoop.hbase.replication.regionserver.Replication";
960  public static final String REPLICATION_SINK_SERVICE_CLASSNAME = "hbase.replication.sink.service";
961  public static final String REPLICATION_SINK_SERVICE_CLASSNAME_DEFAULT =
962    "org.apache.hadoop.hbase.replication.ReplicationSinkServiceImpl";
963  public static final String REPLICATION_BULKLOAD_ENABLE_KEY = "hbase.replication.bulkload.enabled";
964  public static final boolean REPLICATION_BULKLOAD_ENABLE_DEFAULT = false;
965  /** Replication cluster id of source cluster which uniquely identifies itself with peer cluster */
966  public static final String REPLICATION_CLUSTER_ID = "hbase.replication.cluster.id";
967  /**
968   * Max total size of buffered entries in all replication peers. It will prevent server getting OOM
969   * if there are many peers. Default value is 256MB which is four times to default
970   * replication.source.size.capacity.
971   */
972  public static final String REPLICATION_SOURCE_TOTAL_BUFFER_KEY = "replication.total.buffer.quota";
973
974  public static final int REPLICATION_SOURCE_TOTAL_BUFFER_DFAULT = 256 * 1024 * 1024;
975
976  /** Configuration key for ReplicationSource shipeEdits timeout */
977  public static final String REPLICATION_SOURCE_SHIPEDITS_TIMEOUT =
978    "replication.source.shipedits.timeout";
979  public static final int REPLICATION_SOURCE_SHIPEDITS_TIMEOUT_DFAULT = 60000;
980
981  /**
982   * Directory where the source cluster file system client configuration are placed which is used by
983   * sink cluster to copy HFiles from source cluster file system
984   */
985  public static final String REPLICATION_CONF_DIR = "hbase.replication.conf.dir";
986
987  /** Maximum time to retry for a failed bulk load request */
988  public static final String BULKLOAD_MAX_RETRIES_NUMBER = "hbase.bulkload.retries.number";
989
990  public static final String KEY_FOR_HOSTNAME_SEEN_BY_MASTER =
991    "hbase.regionserver.hostname.seen.by.master";
992
993  public static final String HBASE_MASTER_LOGCLEANER_PLUGINS = "hbase.master.logcleaner.plugins";
994
995  public static final String HBASE_REGION_SPLIT_POLICY_KEY =
996    "hbase.regionserver.region.split.policy";
997
998  /** Whether nonces are enabled; default is true. */
999  public static final String HBASE_RS_NONCES_ENABLED = "hbase.regionserver.nonces.enabled";
1000
1001  /**
1002   * Configuration key for the size of the block cache
1003   */
1004  public static final String HFILE_BLOCK_CACHE_SIZE_KEY = "hfile.block.cache.size";
1005
1006  public static final float HFILE_BLOCK_CACHE_SIZE_DEFAULT = 0.4f;
1007
1008  /**
1009   * Configuration key for setting the fix size of the block size, default do nothing and it should
1010   * be explicitly set by user or only used within ClientSideRegionScanner. if it's set less than
1011   * current max on heap size, it overrides the max size of block cache
1012   */
1013  public static final String HFILE_ONHEAP_BLOCK_CACHE_FIXED_SIZE_KEY =
1014    "hfile.onheap.block.cache.fixed.size";
1015  public static final long HFILE_ONHEAP_BLOCK_CACHE_FIXED_SIZE_DEFAULT = 0L;
1016  public static final long HBASE_CLIENT_SCANNER_ONHEAP_BLOCK_CACHE_FIXED_SIZE_DEFAULT =
1017    32 * 1024 * 1024L;
1018
1019  /**
1020   * Configuration key for setting pread must read both necessaryLen and extraLen, default is
1021   * disabled. This is an optimized flag for reading HFile from blob storage.
1022   */
1023  public static final String HFILE_PREAD_ALL_BYTES_ENABLED_KEY = "hfile.pread.all.bytes.enabled";
1024  public static final boolean HFILE_PREAD_ALL_BYTES_ENABLED_DEFAULT = false;
1025
1026  /*
1027   * Minimum percentage of free heap necessary for a successful cluster startup.
1028   */
1029  public static final float HBASE_CLUSTER_MINIMUM_MEMORY_THRESHOLD = 0.2f;
1030
1031  public static final String CP_HTD_ATTR_INCLUSION_KEY =
1032    "hbase.coprocessor.classloader.included.classes";
1033
1034  /** The delay when re-trying a socket operation in a loop (HBASE-4712) */
1035  public static final int SOCKET_RETRY_WAIT_MS = 200;
1036
1037  /** Host name of the local machine */
1038  public static final String LOCALHOST = "localhost";
1039
1040  /**
1041   * If this parameter is set to true, then hbase will read data and then verify checksums. Checksum
1042   * verification inside hdfs will be switched off. However, if the hbase-checksum verification
1043   * fails, then it will switch back to using hdfs checksums for verifiying data that is being read
1044   * from storage. If this parameter is set to false, then hbase will not verify any checksums,
1045   * instead it will depend on checksum verification being done in the hdfs client.
1046   */
1047  public static final String HBASE_CHECKSUM_VERIFICATION = "hbase.regionserver.checksum.verify";
1048
1049  public static final String LOCALHOST_IP = "127.0.0.1";
1050
1051  public static final String REGION_SERVER_HANDLER_COUNT = "hbase.regionserver.handler.count";
1052  public static final int DEFAULT_REGION_SERVER_HANDLER_COUNT = 30;
1053
1054  /*
1055   * REGION_SERVER_HANDLER_ABORT_ON_ERROR_PERCENT: -1 => Disable aborting 0 => Abort if even a
1056   * single handler has died 0.x => Abort only when this percent of handlers have died 1 => Abort
1057   * only all of the handers have died
1058   */
1059  public static final String REGION_SERVER_HANDLER_ABORT_ON_ERROR_PERCENT =
1060    "hbase.regionserver.handler.abort.on.error.percent";
1061  public static final double DEFAULT_REGION_SERVER_HANDLER_ABORT_ON_ERROR_PERCENT = 0.5;
1062
1063  // High priority handlers to deal with admin requests and system table operation requests
1064  public static final String REGION_SERVER_HIGH_PRIORITY_HANDLER_COUNT =
1065    "hbase.regionserver.metahandler.count";
1066  public static final int DEFAULT_REGION_SERVER_HIGH_PRIORITY_HANDLER_COUNT = 20;
1067
1068  public static final String REGION_SERVER_REPLICATION_HANDLER_COUNT =
1069    "hbase.regionserver.replication.handler.count";
1070  public static final int DEFAULT_REGION_SERVER_REPLICATION_HANDLER_COUNT = 3;
1071  public static final String REGION_SERVER_BULKLOAD_HANDLER_COUNT =
1072    "hbase.regionserver.bulkload.handler.count";
1073  public static final int DEFAULT_REGION_SERVER_BULKLOAD_HANDLER_COUNT = 0;
1074  // Meta Transition handlers to deal with meta ReportRegionStateTransitionRequest. Meta transition
1075  // should be dealt with in a separate handler in case blocking other region's transition.
1076  public static final String MASTER_META_TRANSITION_HANDLER_COUNT =
1077    "hbase.master.meta.transition.handler.count";
1078  public static final int MASTER__META_TRANSITION_HANDLER_COUNT_DEFAULT = 1;
1079
1080  /** Conf key for enabling meta replication */
1081  public static final String USE_META_REPLICAS = "hbase.meta.replicas.use";
1082  public static final boolean DEFAULT_USE_META_REPLICAS = false;
1083
1084  /**
1085   * @deprecated Since 2.4.0, will be removed in 4.0.0. Please change the meta replicas number by
1086   *             altering meta table, i.e, set a new 'region replication' number and call
1087   *             modifyTable.
1088   */
1089  @Deprecated
1090  public static final String META_REPLICAS_NUM = "hbase.meta.replica.count";
1091  /**
1092   * @deprecated Since 2.4.0, will be removed in 4.0.0. Please change the meta replicas number by
1093   *             altering meta table, i.e, set a new 'region replication' number and call
1094   *             modifyTable.
1095   */
1096  @Deprecated
1097  public static final int DEFAULT_META_REPLICA_NUM = 1;
1098
1099  /**
1100   * The name of the configuration parameter that specifies the number of bytes in a newly created
1101   * checksum chunk.
1102   */
1103  public static final String BYTES_PER_CHECKSUM = "hbase.hstore.bytes.per.checksum";
1104
1105  /**
1106   * The name of the configuration parameter that specifies the name of an algorithm that is used to
1107   * compute checksums for newly created blocks.
1108   */
1109  public static final String CHECKSUM_TYPE_NAME = "hbase.hstore.checksum.algorithm";
1110
1111  /** Enable file permission modification from standard hbase */
1112  public static final String ENABLE_DATA_FILE_UMASK = "hbase.data.umask.enable";
1113  /** File permission umask to use when creating hbase data files */
1114  public static final String DATA_FILE_UMASK_KEY = "hbase.data.umask";
1115
1116  /** Configuration name of WAL Compression */
1117  public static final String ENABLE_WAL_COMPRESSION = "hbase.regionserver.wal.enablecompression";
1118
1119  /**
1120   * Configuration name of WAL storage policy Valid values are: HOT, COLD, WARM, ALL_SSD, ONE_SSD,
1121   * LAZY_PERSIST See
1122   * http://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-hdfs/ArchivalStorage.html
1123   */
1124  public static final String WAL_STORAGE_POLICY = "hbase.wal.storage.policy";
1125  /**
1126   * "NONE" is not a valid storage policy and means we defer the policy to HDFS. @see
1127   * <a href="https://issues.apache.org/jira/browse/HBASE-20691">HBASE-20691</a>
1128   */
1129  public static final String DEFER_TO_HDFS_STORAGE_POLICY = "NONE";
1130  /** By default we defer the WAL storage policy to HDFS */
1131  public static final String DEFAULT_WAL_STORAGE_POLICY = DEFER_TO_HDFS_STORAGE_POLICY;
1132
1133  /** Region in Transition metrics threshold time */
1134  public static final String METRICS_RIT_STUCK_WARNING_THRESHOLD =
1135    "hbase.metrics.rit.stuck.warning.threshold";
1136
1137  public static final String LOAD_BALANCER_SLOP_KEY = "hbase.regions.slop";
1138
1139  /** delimiter used between portions of a region name */
1140  public static final int DELIMITER = ',';
1141
1142  /**
1143   * QOS attributes: these attributes are used to demarcate RPC call processing by different set of
1144   * handlers. For example, HIGH_QOS tagged methods are handled by high priority handlers.
1145   */
1146  // normal_QOS < replication_QOS < replay_QOS < QOS_threshold < admin_QOS < high_QOS < meta_QOS
1147  public static final int PRIORITY_UNSET = -1;
1148  public static final int NORMAL_QOS = 0;
1149  public static final int REPLICATION_QOS = 5;
1150  public static final int BULKLOAD_QOS = 4;
1151  /**
1152   * @deprecated since 3.0.0, will be removed in 4.0.0. DLR has been purged for a long time and
1153   *             region replication has its own 'replay' method.
1154   */
1155  @Deprecated
1156  public static final int REPLAY_QOS = 6;
1157  public static final int REGION_REPLICATION_QOS = REPLAY_QOS;
1158  public static final int QOS_THRESHOLD = 10;
1159  public static final int ADMIN_QOS = 100;
1160  public static final int HIGH_QOS = 200;
1161  public static final int SYSTEMTABLE_QOS = HIGH_QOS;
1162
1163  /** Directory under /hbase where archived hfiles are stored */
1164  public static final String HFILE_ARCHIVE_DIRECTORY = "archive";
1165
1166  /**
1167   * Name of the directory to store all snapshots. See SnapshotDescriptionUtils for remaining
1168   * snapshot constants; this is here to keep HConstants dependencies at a minimum and
1169   * uni-directional.
1170   */
1171  public static final String SNAPSHOT_DIR_NAME = ".hbase-snapshot";
1172
1173  /* Name of old snapshot directory. See HBASE-8352 for details on why it needs to be renamed */
1174  public static final String OLD_SNAPSHOT_DIR_NAME = ".snapshot";
1175
1176  /** Temporary directory used for table creation and deletion */
1177  public static final String HBASE_TEMP_DIRECTORY = ".tmp";
1178  /**
1179   * The period (in milliseconds) between computing region server point in time metrics
1180   */
1181  public static final String REGIONSERVER_METRICS_PERIOD = "hbase.regionserver.metrics.period";
1182  public static final long DEFAULT_REGIONSERVER_METRICS_PERIOD = 5000;
1183  /** Directories that are not HBase table directories */
1184  public static final List<String> HBASE_NON_TABLE_DIRS = Collections.unmodifiableList(
1185    Arrays.asList(new String[] { HBCK_SIDELINEDIR_NAME, HBASE_TEMP_DIRECTORY, MIGRATION_NAME }));
1186
1187  /**
1188   * Directories that are not HBase user table directories.
1189   * @deprecated Since hbase-2.3.0; no replacement as not used any more (internally at least)
1190   */
1191  @Deprecated
1192  public static final List<String> HBASE_NON_USER_TABLE_DIRS =
1193    Collections.unmodifiableList(Arrays.asList(
1194      (String[]) ArrayUtils.addAll(new String[] { TableName.META_TABLE_NAME.getNameAsString() },
1195        HBASE_NON_TABLE_DIRS.toArray())));
1196
1197  /** Health script related settings. */
1198  public static final String HEALTH_SCRIPT_LOC = "hbase.node.health.script.location";
1199  public static final String HEALTH_SCRIPT_TIMEOUT = "hbase.node.health.script.timeout";
1200  public static final String HEALTH_CHORE_WAKE_FREQ = "hbase.node.health.script.frequency";
1201  public static final long DEFAULT_HEALTH_SCRIPT_TIMEOUT = 60000;
1202  /**
1203   * The maximum number of health check failures a server can encounter consecutively.
1204   */
1205  public static final String HEALTH_FAILURE_THRESHOLD = "hbase.node.health.failure.threshold";
1206  public static final int DEFAULT_HEALTH_FAILURE_THRESHOLD = 3;
1207
1208  public static final String EXECUTOR_STATUS_COLLECT_ENABLED =
1209    "hbase.executors.status.collect.enabled";
1210  public static final boolean DEFAULT_EXECUTOR_STATUS_COLLECT_ENABLED = true;
1211
1212  /**
1213   * Setting to activate, or not, the publication of the status by the master. Default notification
1214   * is by a multicast message.
1215   */
1216  public static final String STATUS_PUBLISHED = "hbase.status.published";
1217  public static final boolean STATUS_PUBLISHED_DEFAULT = false;
1218
1219  /**
1220   * IP to use for the multicast status messages between the master and the clients. The default
1221   * address is chosen as one among others within the ones suitable for multicast messages.
1222   */
1223  public static final String STATUS_MULTICAST_ADDRESS = "hbase.status.multicast.address.ip";
1224  public static final String DEFAULT_STATUS_MULTICAST_ADDRESS = "226.1.1.3";
1225
1226  /**
1227   * The address to use for binding the local socket for receiving multicast. Defaults to 0.0.0.0.
1228   * @see <a href="https://issues.apache.org/jira/browse/HBASE-9961">HBASE-9961</a>
1229   */
1230  public static final String STATUS_MULTICAST_BIND_ADDRESS =
1231    "hbase.status.multicast.bind.address.ip";
1232  public static final String DEFAULT_STATUS_MULTICAST_BIND_ADDRESS = "0.0.0.0";
1233
1234  /**
1235   * The port to use for the multicast messages.
1236   */
1237  public static final String STATUS_MULTICAST_PORT = "hbase.status.multicast.address.port";
1238  public static final int DEFAULT_STATUS_MULTICAST_PORT = 16100;
1239
1240  /**
1241   * The network interface name to use for the multicast messages.
1242   */
1243  public static final String STATUS_MULTICAST_NI_NAME = "hbase.status.multicast.ni.name";
1244
1245  /**
1246   * The address to use for binding the local socket for sending multicast. Defaults to 0.0.0.0.
1247   */
1248  public static final String STATUS_MULTICAST_PUBLISHER_BIND_ADDRESS =
1249    "hbase.status.multicast.publisher.bind.address.ip";
1250  public static final String DEFAULT_STATUS_MULTICAST_PUBLISHER_BIND_ADDRESS = "0.0.0.0";
1251
1252  public static final long NO_NONCE = 0;
1253
1254  /** Default cipher for encryption */
1255  public static final String CIPHER_AES = "AES";
1256
1257  /** Configuration key for the crypto algorithm provider, a class name */
1258  public static final String CRYPTO_CIPHERPROVIDER_CONF_KEY = "hbase.crypto.cipherprovider";
1259
1260  /** Configuration key for the crypto key provider, a class name */
1261  public static final String CRYPTO_KEYPROVIDER_CONF_KEY = "hbase.crypto.keyprovider";
1262
1263  /** Configuration key for the crypto key provider parameters */
1264  public static final String CRYPTO_KEYPROVIDER_PARAMETERS_KEY =
1265    "hbase.crypto.keyprovider.parameters";
1266
1267  /** Configuration key for the name of the master key for the cluster, a string */
1268  public static final String CRYPTO_MASTERKEY_NAME_CONF_KEY = "hbase.crypto.master.key.name";
1269
1270  /** Configuration key for the name of the alternate master key for the cluster, a string */
1271  public static final String CRYPTO_MASTERKEY_ALTERNATE_NAME_CONF_KEY =
1272    "hbase.crypto.master.alternate.key.name";
1273
1274  /** Configuration key for the algorithm to use when encrypting the WAL, a string */
1275  public static final String CRYPTO_WAL_ALGORITHM_CONF_KEY = "hbase.crypto.wal.algorithm";
1276
1277  /** Configuration key for the name of the master WAL encryption key for the cluster, a string */
1278  public static final String CRYPTO_WAL_KEY_NAME_CONF_KEY = "hbase.crypto.wal.key.name";
1279
1280  /** Configuration key for the algorithm used for creating jks key, a string */
1281  public static final String CRYPTO_KEY_ALGORITHM_CONF_KEY = "hbase.crypto.key.algorithm";
1282
1283  /** Configuration key for the name of the alternate cipher algorithm for the cluster, a string */
1284  public static final String CRYPTO_ALTERNATE_KEY_ALGORITHM_CONF_KEY =
1285    "hbase.crypto.alternate.key.algorithm";
1286
1287  /** Configuration key for enabling WAL encryption, a boolean */
1288  public static final String ENABLE_WAL_ENCRYPTION = "hbase.regionserver.wal.encryption";
1289
1290  /** Configuration key for setting RPC codec class name */
1291  public static final String RPC_CODEC_CONF_KEY = "hbase.client.rpc.codec";
1292
1293  /** Configuration key for setting replication codec class name */
1294  public static final String REPLICATION_CODEC_CONF_KEY = "hbase.replication.rpc.codec";
1295
1296  /** Maximum number of threads used by the replication source for shipping edits to the sinks */
1297  public static final String REPLICATION_SOURCE_MAXTHREADS_KEY =
1298    "hbase.replication.source.maxthreads";
1299
1300  /**
1301   * Drop edits for tables that been deleted from the replication source and target
1302   * @deprecated since 3.0.0. Will be removed in 4.0.0. Moved it into
1303   *             HBaseInterClusterReplicationEndpoint.
1304   * @see <a href="https://issues.apache.org/jira/browse/HBASE-24359">HBASE-24359</a>
1305   */
1306  @Deprecated
1307  public static final String REPLICATION_DROP_ON_DELETED_TABLE_KEY =
1308    "hbase.replication.drop.on.deleted.table";
1309
1310  /** Maximum number of threads used by the replication source for shipping edits to the sinks */
1311  public static final int REPLICATION_SOURCE_MAXTHREADS_DEFAULT = 10;
1312
1313  /** Configuration key for SplitLog manager timeout */
1314  public static final String HBASE_SPLITLOG_MANAGER_TIMEOUT = "hbase.splitlog.manager.timeout";
1315
1316  /**
1317   * Configuration keys for Bucket cache
1318   */
1319  // TODO moving these bucket cache implementation specific configs to this level is violation of
1320  // encapsulation. But as these has to be referred from hbase-common and bucket cache
1321  // sits in hbase-server, there were no other go! Can we move the cache implementation to
1322  // hbase-common?
1323
1324  /**
1325   * Current ioengine options in include: heap, offheap and file:PATH (where PATH is the path to the
1326   * file that will host the file-based cache. See BucketCache#getIOEngineFromName() for list of
1327   * supported ioengine options.
1328   * <p>
1329   * Set this option and a non-zero {@link #BUCKET_CACHE_SIZE_KEY} to enable bucket cache.
1330   */
1331  public static final String BUCKET_CACHE_IOENGINE_KEY = "hbase.bucketcache.ioengine";
1332
1333  /**
1334   * When using bucket cache, it is the capacity in megabytes of the cache.
1335   */
1336  public static final String BUCKET_CACHE_SIZE_KEY = "hbase.bucketcache.size";
1337
1338  /**
1339   * HConstants for fast fail on the client side follow
1340   */
1341  /**
1342   * Config for enabling/disabling the fast fail mode.
1343   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1344   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1345   */
1346  @Deprecated
1347  public static final String HBASE_CLIENT_FAST_FAIL_MODE_ENABLED =
1348    "hbase.client.fast.fail.mode.enabled";
1349
1350  /**
1351   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1352   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1353   */
1354  @Deprecated
1355  public static final boolean HBASE_CLIENT_ENABLE_FAST_FAIL_MODE_DEFAULT = false;
1356
1357  /**
1358   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1359   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1360   */
1361  @Deprecated
1362  public static final String HBASE_CLIENT_FAST_FAIL_THREASHOLD_MS =
1363    "hbase.client.fastfail.threshold";
1364
1365  /**
1366   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1367   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1368   */
1369  @Deprecated
1370  public static final long HBASE_CLIENT_FAST_FAIL_THREASHOLD_MS_DEFAULT = 60000;
1371
1372  /**
1373   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1374   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1375   */
1376  @Deprecated
1377  public static final String HBASE_CLIENT_FAILURE_MAP_CLEANUP_INTERVAL_MS =
1378    "hbase.client.failure.map.cleanup.interval";
1379
1380  /**
1381   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1382   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1383   */
1384  @Deprecated
1385  public static final long HBASE_CLIENT_FAILURE_MAP_CLEANUP_INTERVAL_MS_DEFAULT = 600000;
1386
1387  /**
1388   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1389   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1390   */
1391  @Deprecated
1392  public static final String HBASE_CLIENT_FAST_FAIL_CLEANUP_MS_DURATION_MS =
1393    "hbase.client.fast.fail.cleanup.duration";
1394
1395  /**
1396   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1397   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1398   */
1399  @Deprecated
1400  public static final long HBASE_CLIENT_FAST_FAIL_CLEANUP_DURATION_MS_DEFAULT = 600000;
1401
1402  /**
1403   * @deprecated since 2.3.0, and in 3.0.0 the actually implementation will be removed so config
1404   *             this value will have no effect. The constants itself will be removed in 4.0.0.
1405   */
1406  @Deprecated
1407  public static final String HBASE_CLIENT_FAST_FAIL_INTERCEPTOR_IMPL =
1408    "hbase.client.fast.fail.interceptor.impl";
1409
1410  /**
1411   * @deprecated since 2.4.0 and in 3.0.0, to be removed in 4.0.0, replaced by procedure-based
1412   *             distributed WAL splitter; see SplitWALManager.
1413   */
1414  @Deprecated
1415  public static final String HBASE_SPLIT_WAL_COORDINATED_BY_ZK = "hbase.split.wal.zk.coordinated";
1416
1417  /**
1418   * @deprecated since 2.4.0 and in 3.0.0, to be removed in 4.0.0.
1419   */
1420  @Deprecated
1421  public static final boolean DEFAULT_HBASE_SPLIT_COORDINATED_BY_ZK = false;
1422
1423  public static final String HBASE_SPLIT_WAL_MAX_SPLITTER = "hbase.regionserver.wal.max.splitters";
1424
1425  public static final int DEFAULT_HBASE_SPLIT_WAL_MAX_SPLITTER = 2;
1426
1427  /**
1428   * Config key for if the server should send backpressure and if the client should listen to that
1429   * backpressure from the server
1430   */
1431  public static final String ENABLE_CLIENT_BACKPRESSURE = "hbase.client.backpressure.enabled";
1432  public static final boolean DEFAULT_ENABLE_CLIENT_BACKPRESSURE = false;
1433
1434  public static final String HEAP_OCCUPANCY_LOW_WATERMARK_KEY =
1435    "hbase.heap.occupancy.low_water_mark";
1436  public static final float DEFAULT_HEAP_OCCUPANCY_LOW_WATERMARK = 0.95f;
1437  public static final String HEAP_OCCUPANCY_HIGH_WATERMARK_KEY =
1438    "hbase.heap.occupancy.high_water_mark";
1439  public static final float DEFAULT_HEAP_OCCUPANCY_HIGH_WATERMARK = 0.98f;
1440
1441  /**
1442   * The max number of threads used for splitting storefiles in parallel during the region split
1443   * process.
1444   */
1445  public static final String REGION_SPLIT_THREADS_MAX =
1446    "hbase.regionserver.region.split.threads.max";
1447
1448  /** Canary config keys */
1449  // TODO: Move these defines to Canary Class
1450  public static final String HBASE_CANARY_WRITE_DATA_TTL_KEY = "hbase.canary.write.data.ttl";
1451
1452  public static final String HBASE_CANARY_WRITE_PERSERVER_REGIONS_LOWERLIMIT_KEY =
1453    "hbase.canary.write.perserver.regions.lowerLimit";
1454
1455  public static final String HBASE_CANARY_WRITE_PERSERVER_REGIONS_UPPERLIMIT_KEY =
1456    "hbase.canary.write.perserver.regions.upperLimit";
1457
1458  public static final String HBASE_CANARY_WRITE_VALUE_SIZE_KEY = "hbase.canary.write.value.size";
1459
1460  public static final String HBASE_CANARY_WRITE_TABLE_CHECK_PERIOD_KEY =
1461    "hbase.canary.write.table.check.period";
1462
1463  public static final String HBASE_CANARY_READ_RAW_SCAN_KEY = "hbase.canary.read.raw.enabled";
1464
1465  public static final String HBASE_CANARY_READ_ALL_CF = "hbase.canary.read.all.column.famliy";
1466  /**
1467   * Configuration keys for programmatic JAAS configuration for secured ZK interaction
1468   */
1469  public static final String ZK_CLIENT_KEYTAB_FILE = "hbase.zookeeper.client.keytab.file";
1470  public static final String ZK_CLIENT_KERBEROS_PRINCIPAL =
1471    "hbase.zookeeper.client.kerberos.principal";
1472  public static final String ZK_SERVER_KEYTAB_FILE = "hbase.zookeeper.server.keytab.file";
1473  public static final String ZK_SERVER_KERBEROS_PRINCIPAL =
1474    "hbase.zookeeper.server.kerberos.principal";
1475
1476  /** Config key for hbase temporary directory in hdfs */
1477  public static final String TEMPORARY_FS_DIRECTORY_KEY = "hbase.fs.tmp.dir";
1478
1479  /**
1480   * Don't use it! This'll get you the wrong path in a secure cluster. Use
1481   * FileSystem.getHomeDirectory() or "/user/" +
1482   * UserGroupInformation.getCurrentUser().getShortUserName()
1483   */
1484  public static final String DEFAULT_TEMPORARY_HDFS_DIRECTORY =
1485    "/user/" + System.getProperty("user.name") + "/hbase-staging";
1486
1487  public static final String SNAPSHOT_RESTORE_TAKE_FAILSAFE_SNAPSHOT =
1488    "hbase.snapshot.restore.take.failsafe.snapshot";
1489  public static final boolean DEFAULT_SNAPSHOT_RESTORE_TAKE_FAILSAFE_SNAPSHOT = true;
1490
1491  public static final String SNAPSHOT_RESTORE_FAILSAFE_NAME =
1492    "hbase.snapshot.restore.failsafe.name";
1493  public static final String DEFAULT_SNAPSHOT_RESTORE_FAILSAFE_NAME =
1494    "hbase-failsafe-{snapshot.name}-{restore.timestamp}";
1495
1496  public static final String DEFAULT_LOSSY_COUNTING_ERROR_RATE =
1497    "hbase.util.default.lossycounting.errorrate";
1498  public static final String NOT_IMPLEMENTED = "Not implemented";
1499
1500  // Default TTL - FOREVER
1501  public static final long DEFAULT_SNAPSHOT_TTL = 0;
1502
1503  // User defined Default TTL config key
1504  public static final String DEFAULT_SNAPSHOT_TTL_CONFIG_KEY = "hbase.master.snapshot.ttl";
1505
1506  // Regions Recovery based on high storeFileRefCount threshold value
1507  public static final String STORE_FILE_REF_COUNT_THRESHOLD =
1508    "hbase.regions.recovery.store.file.ref.count";
1509
1510  // default -1 indicates there is no threshold on high storeRefCount
1511  public static final int DEFAULT_STORE_FILE_REF_COUNT_THRESHOLD = -1;
1512
1513  public static final String REGIONS_RECOVERY_INTERVAL =
1514    "hbase.master.regions.recovery.check.interval";
1515
1516  public static final int DEFAULT_REGIONS_RECOVERY_INTERVAL = 1200 * 1000; // Default 20 min
1517
1518  /**
1519   * Configurations for master executor services.
1520   */
1521  public static final String MASTER_OPEN_REGION_THREADS =
1522    "hbase.master.executor.openregion.threads";
1523  public static final int MASTER_OPEN_REGION_THREADS_DEFAULT = 5;
1524
1525  public static final String MASTER_CLOSE_REGION_THREADS =
1526    "hbase.master.executor.closeregion.threads";
1527  public static final int MASTER_CLOSE_REGION_THREADS_DEFAULT = 5;
1528
1529  public static final String MASTER_SERVER_OPERATIONS_THREADS =
1530    "hbase.master.executor.serverops.threads";
1531  public static final int MASTER_SERVER_OPERATIONS_THREADS_DEFAULT = 5;
1532
1533  /**
1534   * Number of threads used to dispatch merge operations to the regionservers.
1535   */
1536  public static final String MASTER_MERGE_DISPATCH_THREADS =
1537    "hbase.master.executor.merge.dispatch.threads";
1538  public static final int MASTER_MERGE_DISPATCH_THREADS_DEFAULT = 2;
1539
1540  public static final String MASTER_META_SERVER_OPERATIONS_THREADS =
1541    "hbase.master.executor.meta.serverops.threads";
1542  public static final int MASTER_META_SERVER_OPERATIONS_THREADS_DEFAULT = 5;
1543
1544  public static final String MASTER_LOG_REPLAY_OPS_THREADS =
1545    "hbase.master.executor.logreplayops.threads";
1546  public static final int MASTER_LOG_REPLAY_OPS_THREADS_DEFAULT = 10;
1547
1548  public static final int DEFAULT_SLOW_LOG_RING_BUFFER_SIZE = 256;
1549
1550  public static final String SLOW_LOG_BUFFER_ENABLED_KEY =
1551    "hbase.regionserver.slowlog.buffer.enabled";
1552  public static final boolean DEFAULT_ONLINE_LOG_PROVIDER_ENABLED = false;
1553
1554  /** The slowlog info family as a string */
1555  private static final String SLOWLOG_INFO_FAMILY_STR = "info";
1556
1557  /** The slowlog info family */
1558  public static final byte[] SLOWLOG_INFO_FAMILY = Bytes.toBytes(SLOWLOG_INFO_FAMILY_STR);
1559
1560  public static final String SLOW_LOG_SYS_TABLE_ENABLED_KEY =
1561    "hbase.regionserver.slowlog.systable.enabled";
1562  public static final boolean DEFAULT_SLOW_LOG_SYS_TABLE_ENABLED_KEY = false;
1563
1564  @Deprecated
1565  // since <need to know the version number> and will be removed in <version number>
1566  // Instead use hbase.regionserver.named.queue.chore.duration config property
1567  public static final String SLOW_LOG_SYS_TABLE_CHORE_DURATION_KEY =
1568    "hbase.slowlog.systable.chore.duration";
1569  // Default 10 mins.
1570  public static final int DEFAULT_SLOW_LOG_SYS_TABLE_CHORE_DURATION = 10 * 60 * 1000;
1571
1572  public static final String SLOW_LOG_SCAN_PAYLOAD_ENABLED = "hbase.slowlog.scan.payload.enabled";
1573  public static final boolean SLOW_LOG_SCAN_PAYLOAD_ENABLED_DEFAULT = false;
1574
1575  public static final String SHELL_TIMESTAMP_FORMAT_EPOCH_KEY =
1576    "hbase.shell.timestamp.format.epoch";
1577
1578  public static final boolean DEFAULT_SHELL_TIMESTAMP_FORMAT_EPOCH = false;
1579
1580  /**
1581   * Number of rows in a batch operation above which a warning will be logged.
1582   */
1583  public static final String BATCH_ROWS_THRESHOLD_NAME = "hbase.rpc.rows.warning.threshold";
1584
1585  /**
1586   * Default value of {@link #BATCH_ROWS_THRESHOLD_NAME}
1587   */
1588  public static final int BATCH_ROWS_THRESHOLD_DEFAULT = 5000;
1589
1590  /**
1591   * In some scenarios, such as the elastic scaling scenario on the cloud, the HBase client may not
1592   * be able to resolve the hostname of the newly added node. If the network is interconnected, the
1593   * client can actually access the HBase cluster nodes through ip. However, since the HBase client
1594   * obtains the Master/RS address info from or the ZK or the meta table, so the Master/RS of the
1595   * HBase cluster needs to expose the service with ip instead of the hostname. Therefore, We can
1596   * use hostname by default, but at the same time, we can also provide a config to support whether
1597   * to use ip for Master/RS service. See HBASE-27304 for details.
1598   */
1599  public final static String HBASE_SERVER_USEIP_ENABLED_KEY = "hbase.server.useip.enabled";
1600
1601  /**
1602   * Default value of {@link #HBASE_SERVER_USEIP_ENABLED_KEY}
1603   */
1604  public final static boolean HBASE_SERVER_USEIP_ENABLED_DEFAULT = false;
1605
1606  private HConstants() {
1607    // Can't be instantiated with this ctor.
1608  }
1609}