FlushSnapshotSubprocedure (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.procedure.Subprocedure
- - org.apache.hadoop.hbase.regionserver.snapshot.FlushSnapshotSubprocedure

All Implemented Interfaces:

Callable<Void>
```
@InterfaceAudience.Private
@InterfaceStability.Unstable
public class FlushSnapshotSubprocedure
extends Subprocedure
```
This online snapshot implementation uses the distributed procedure framework to force a store flush and then records the hfiles. Its enter stage does nothing. Its leave stage then flushes the memstore, builds the region server's snapshot manifest from its hfiles list, and copies .regioninfos into the snapshot working directory. At the master side, there is an atomic rename of the working dir into the proper snapshot directory.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

private class FlushSnapshotSubprocedure.RegionSnapshotTask
Callable for adding files to snapshot manifest working dir.
- Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure.Subprocedure
  Subprocedure.SubprocedureImpl

Nested Classes
Modifier and Type	Class and Description
`private class`	`FlushSnapshotSubprocedure.RegionSnapshotTask` Callable for adding files to snapshot manifest working dir.

Field Summary

Fields
Modifier and Type	Field and Description
`private static org.apache.commons.logging.Log`	`LOG`
`(package private) static int`	`MAX_RETRIES`
`private List<Region>`	`regions`
`private org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription`	`snapshot`
`private boolean`	`snapshotSkipFlush`
`private RegionServerSnapshotManager.SnapshotSubprocedurePool`	`taskManager`

Fields inherited from class org.apache.hadoop.hbase.procedure.Subprocedure
executionTimeoutTimer, monitor, rpcs, wakeFrequency

Constructor Summary

Constructors
Constructor and Description
`FlushSnapshotSubprocedure(ProcedureMember member, ForeignExceptionDispatcher errorListener, long wakeFrequency, long timeout, List<Region> regions, org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot, RegionServerSnapshotManager.SnapshotSubprocedurePool taskManager)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`acquireBarrier()` do nothing, core of snapshot is executed in `insideBarrier()` step.
`void`	`cleanup(Exception e)` Cancel threads if they haven't finished.
`private void`	`flushSnapshot()`
`byte[]`	`insideBarrier()` do a flush snapshot of every region on this rs from the target table.
`void`	`releaseBarrier()` Hooray!

Methods inherited from class org.apache.hadoop.hbase.procedure.Subprocedure
call, cancel, getMemberName, getName, receiveReachedGlobalBarrier, waitForLocallyCompleted

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

private static final org.apache.commons.logging.Log LOG

regions
```
private final List<Region> regions
```

snapshot

private final org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot

taskManager

private final RegionServerSnapshotManager.SnapshotSubprocedurePool taskManager

snapshotSkipFlush
```
private boolean snapshotSkipFlush
```

MAX_RETRIES
```
static final int MAX_RETRIES
```
See Also:
Constant Field Values

Constructor Detail

FlushSnapshotSubprocedure

public FlushSnapshotSubprocedure(ProcedureMember member,
                         ForeignExceptionDispatcher errorListener,
                         long wakeFrequency,
                         long timeout,
                         List<Region> regions,
                         org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot,
                         RegionServerSnapshotManager.SnapshotSubprocedurePool taskManager)

Method Detail
- flushSnapshot
```
private void flushSnapshot()
                    throws ForeignException
```
  Throws:
  
  ForeignException
- acquireBarrier
```
public void acquireBarrier()
                    throws ForeignException
```
  do nothing, core of snapshot is executed in insideBarrier() step.
  
  Specified by:
  
  acquireBarrier in class Subprocedure
  
  Throws:
  
  ForeignException
- insideBarrier
```
public byte[] insideBarrier()
                     throws ForeignException
```
  do a flush snapshot of every region on this rs from the target table.
  
  Specified by:
  
  insideBarrier in class Subprocedure
  
  Returns:
  the data the subprocedure wants to return to coordinator side.
  
  Throws:
  
  ForeignException
- cleanup
```
public void cleanup(Exception e)
```
  Cancel threads if they haven't finished.
  
  Specified by:
  
  cleanup in class Subprocedure
- releaseBarrier
```
public void releaseBarrier()
```
  Hooray!

Class FlushSnapshotSubprocedure

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure.Subprocedure

Field Summary

Fields inherited from class org.apache.hadoop.hbase.procedure.Subprocedure

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.procedure.Subprocedure

Methods inherited from class java.lang.Object

Field Detail

LOG

regions

snapshot

taskManager

snapshotSkipFlush

MAX_RETRIES

Constructor Detail

FlushSnapshotSubprocedure

Method Detail

flushSnapshot

acquireBarrier

insideBarrier

cleanup

releaseBarrier