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.quotas;
019
020import org.apache.yetus.audience.InterfaceAudience;
021import org.apache.yetus.audience.InterfaceStability;
022
023/**
024 * Internal interface used to interact with the user/table quota.
025 */
026@InterfaceAudience.Private
027@InterfaceStability.Evolving
028public interface QuotaLimiter {
029  /**
030   * Checks if it is possible to execute the specified operation.
031   * @param writeReqs                 the write requests that will be checked against the available
032   *                                  quota
033   * @param estimateWriteSize         the write size that will be checked against the available
034   *                                  quota
035   * @param readReqs                  the read requests that will be checked against the available
036   *                                  quota
037   * @param estimateReadSize          the read size that will be checked against the available quota
038   * @param estimateWriteCapacityUnit the write capacity unit that will be checked against the
039   *                                  available quota
040   * @param estimateReadCapacityUnit  the read capacity unit that will be checked against the
041   *                                  available quota
042   * @throws RpcThrottlingException thrown if not enough available resources to perform operation.
043   */
044  void checkQuota(long writeReqs, long estimateWriteSize, long readReqs, long estimateReadSize,
045    long estimateWriteCapacityUnit, long estimateReadCapacityUnit, boolean isAtomic)
046    throws RpcThrottlingException;
047
048  /**
049   * Removes the specified write and read amount from the quota. At this point the write and read
050   * amount will be an estimate, that will be later adjusted with a consumeWrite()/consumeRead()
051   * call.
052   * @param writeReqs         the write requests that will be removed from the current quota
053   * @param writeSize         the write size that will be removed from the current quota
054   * @param readReqs          the read requests that will be removed from the current quota
055   * @param readSize          the read size that will be removed from the current quota
056   * @param writeCapacityUnit the write capacity unit that will be removed from the current quota
057   * @param readCapacityUnit  the read capacity unit num that will be removed from the current quota
058   */
059  void grabQuota(long writeReqs, long writeSize, long readReqs, long readSize,
060    long writeCapacityUnit, long readCapacityUnit, boolean isAtomic);
061
062  /**
063   * Removes or add back some write amount to the quota. (called at the end of an operation in case
064   * the estimate quota was off)
065   */
066  void consumeWrite(long size, long capacityUnit, boolean isAtomic);
067
068  /**
069   * Removes or add back some read amount to the quota. (called at the end of an operation in case
070   * the estimate quota was off)
071   */
072  void consumeRead(long size, long capacityUnit, boolean isAtomic);
073
074  /** Returns true if the limiter is a noop */
075  boolean isBypass();
076
077  /** Returns the number of bytes available to read to avoid exceeding the quota */
078  long getReadAvailable();
079
080  /** Returns the maximum number of bytes ever available to read */
081  long getReadLimit();
082
083  /** Returns the maximum number of bytes ever available to write */
084  long getWriteLimit();
085
086  /** Returns the number of bytes available to write to avoid exceeding the quota */
087  long getWriteAvailable();
088
089  /** Returns the maximum number of requests to allow per TimeUnit */
090  long getRequestNumLimit();
091
092  /** Returns the maximum number of reads to allow per TimeUnit */
093  long getReadNumLimit();
094
095  /** Returns the maximum number of writes to allow per TimeUnit */
096  long getWriteNumLimit();
097
098}