CommitLog (apache-cassandra API)

java.lang.Object
- org.apache.cassandra.db.commitlog.CommitLog

All Implemented Interfaces:: CommitLogMBean

public class CommitLog
extends java.lang.Object
implements CommitLogMBean

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class CommitLog.Configuration

Nested Classes
Modifier and Type	Class and Description
`static class`	`CommitLog.Configuration`

Field Summary

Fields
Modifier and Type Field and Description

CommitLogArchiver archiver

static CommitLog instance

CommitLogMetrics metrics

AbstractCommitLogSegmentManager segmentManager

Fields
Modifier and Type	Field and Description
`CommitLogArchiver`	`archiver`
`static CommitLog`	`instance`
`CommitLogMetrics`	`metrics`
`AbstractCommitLogSegmentManager`	`segmentManager`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`CommitLogPosition`	`add(Mutation mutation)` Add a Mutation to the commit log.
`void`	`discardCompletedSegments(TableId id, CommitLogPosition lowerBound, CommitLogPosition upperBound)` Modifies the per-CF dirty cursors of any commit log segments for the column family according to the position given.
`void`	`forceRecycleAllSegments()` Flushes all dirty CFs, waiting for them to free and recycle any segments they were retaining
`void`	`forceRecycleAllSegments(java.lang.Iterable<TableId> droppedTables)` Flushes all dirty CFs, waiting for them to free and recycle any segments they were retaining
`static long`	`freeDiskSpace()`
`long`	`getActiveContentSize()`
`long`	`getActiveOnDiskSize()`
`java.util.Map<java.lang.String,java.lang.Double>`	`getActiveSegmentCompressionRatios()`
`java.util.List<java.lang.String>`	`getActiveSegmentNames()`
`java.lang.String`	`getArchiveCommand()` Command to execute to archive a commitlog segment.
`java.util.List<java.lang.String>`	`getArchivingSegmentNames()`
`CommitLogPosition`	`getCurrentPosition()`
`java.lang.String`	`getRestoreCommand()` Command to execute to make an archived commitlog live again
`java.lang.String`	`getRestoreDirectories()` Directory to scan the recovery files in
`long`	`getRestorePointInTime()` Restore mutations created up to and including this timestamp in GMT There are only three different formats to express three time precisions: Seconds, Milliseconds, and Microseconds.
`java.lang.String`	`getRestorePrecision()` get precision of the timestamp used in the restore (MILLISECONDS, MICROSECONDS, ...) to determine if passed the restore point in time.
`java.io.File[]`	`getUnmanagedFiles()`
`static boolean`	`handleCommitError(java.lang.String message, java.lang.Throwable t)`
`boolean`	`hasFilesToReplay()`
`boolean`	`isStarted()`
`void`	`recover(java.lang.String path)` Perform recovery on a single commit log.
`int`	`recoverFiles(java.io.File... clogs)` Perform recovery on a list of commit log files.
`void`	`recoverPath(java.lang.String path)`
`int`	`recoverSegmentsOnDisk()` Perform recovery on commit logs located in the directory specified by the config file.
`void`	`requestExtraSync()` Preempts the CLExecutor, telling to to sync immediately
`void`	`resetConfiguration()` FOR TESTING PURPOSES.
`int`	`resetUnsafe(boolean deleteSegments)` FOR TESTING PURPOSES
`int`	`restartUnsafe()` FOR TESTING PURPOSES
`void`	`setCommitlogArchiver(CommitLogArchiver archiver)`
`void`	`shutdownBlocking()` Shuts down the threads used by the commit log, blocking until completion.
`CommitLog`	`start()` Tries to start the CommitLog if not already started.
`void`	`stopUnsafe(boolean deleteSegments)` FOR TESTING PURPOSES
`void`	`sync(boolean flush)` Forces a disk flush on the commit log files that need it.

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

- Field Detail
  - instance
```
public static final CommitLog instance
```
  - segmentManager
```
public final AbstractCommitLogSegmentManager segmentManager
```
  - archiver
```
public CommitLogArchiver archiver
```
  - metrics
```
public final CommitLogMetrics metrics
```
- Method Detail
  - start
```
public CommitLog start()
```
    Tries to start the CommitLog if not already started.
  - isStarted
```
public boolean isStarted()
```
  - hasFilesToReplay
```
public boolean hasFilesToReplay()
```
  - getUnmanagedFiles
```
public java.io.File[] getUnmanagedFiles()
```
  - recoverSegmentsOnDisk
```
public int recoverSegmentsOnDisk()
                          throws java.io.IOException
```
    Perform recovery on commit logs located in the directory specified by the config file.
    
    Returns:
    
    the number of mutations replayed
    
    Throws:
    
    java.io.IOException
  - recoverFiles
```
public int recoverFiles(java.io.File... clogs)
                 throws java.io.IOException
```
    Perform recovery on a list of commit log files.
    
    Parameters:
    
    clogs - the list of commit log files to replay
    
    Returns:
    
    the number of mutations replayed
    
    Throws:
    
    java.io.IOException
  - recoverPath
```
public void recoverPath(java.lang.String path)
                 throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - recover
```
public void recover(java.lang.String path)
             throws java.io.IOException
```
    Perform recovery on a single commit log. Kept w/sub-optimal name due to coupling w/MBean / JMX
    
    Specified by:
    
    recover in interface CommitLogMBean
    
    Throws:
    
    java.io.IOException
  - getCurrentPosition
```
public CommitLogPosition getCurrentPosition()
```
    Returns:
    
    a CommitLogPosition which, if >= one returned from add(), implies add() was started (but not necessarily finished) prior to this call
  - forceRecycleAllSegments
```
public void forceRecycleAllSegments(java.lang.Iterable<TableId> droppedTables)
```
    Flushes all dirty CFs, waiting for them to free and recycle any segments they were retaining
  - forceRecycleAllSegments
```
public void forceRecycleAllSegments()
```
    Flushes all dirty CFs, waiting for them to free and recycle any segments they were retaining
  - sync
```
public void sync(boolean flush)
          throws java.io.IOException
```
    Forces a disk flush on the commit log files that need it. Blocking.
    
    Throws:
    
    java.io.IOException
  - requestExtraSync
```
public void requestExtraSync()
```
    Preempts the CLExecutor, telling to to sync immediately
  - add
```
public CommitLogPosition add(Mutation mutation)
                      throws CDCWriteException
```
    Add a Mutation to the commit log. If CDC is enabled, this can fail.
    
    Parameters:
    
    mutation - the Mutation to add to the log
    
    Throws:
    
    CDCWriteException
  - discardCompletedSegments
```
public void discardCompletedSegments(TableId id,
                                     CommitLogPosition lowerBound,
                                     CommitLogPosition upperBound)
```
    Modifies the per-CF dirty cursors of any commit log segments for the column family according to the position given. Discards any commit log segments that are no longer used.
    
    Parameters:
    
    id - the table that was flushed
    
    lowerBound - the lowest covered replay position of the flush
    
    lowerBound - the highest covered replay position of the flush
  - getArchiveCommand
```
public java.lang.String getArchiveCommand()
```
    Description copied from interface: CommitLogMBean
    
    Command to execute to archive a commitlog segment. Blank to disabled.
    
    Specified by:
    
    getArchiveCommand in interface CommitLogMBean
  - getRestoreCommand
```
public java.lang.String getRestoreCommand()
```
    Description copied from interface: CommitLogMBean
    
    Command to execute to make an archived commitlog live again
    
    Specified by:
    
    getRestoreCommand in interface CommitLogMBean
  - getRestoreDirectories
```
public java.lang.String getRestoreDirectories()
```
    Description copied from interface: CommitLogMBean
    
    Directory to scan the recovery files in
    
    Specified by:
    
    getRestoreDirectories in interface CommitLogMBean
  - getRestorePointInTime
```
public long getRestorePointInTime()
```
    Description copied from interface: CommitLogMBean
    
    Restore mutations created up to and including this timestamp in GMT There are only three different formats to express three time precisions: Seconds, Milliseconds, and Microseconds. Seconds format: yyyy:MM:dd HH:mm:ss (2012:04:31 20:43:12) Milliseconds format: yyyy:MM:dd HH:mm:ss.SSS (2012:04:31 20:43:12.633) Microseconds format: yyyy:MM:dd HH:mm:ss.SSSSSS (2012:04:31 20:43:12.633222) Recovery will continue through the segment when the first client-supplied timestamp greater than this time is encountered, but only mutations less than or equal to this timestamp will be applied.
    
    Specified by:
    
    getRestorePointInTime in interface CommitLogMBean
  - getRestorePrecision
```
public java.lang.String getRestorePrecision()
```
    Description copied from interface: CommitLogMBean
    
    get precision of the timestamp used in the restore (MILLISECONDS, MICROSECONDS, ...) to determine if passed the restore point in time.
    
    Specified by:
    
    getRestorePrecision in interface CommitLogMBean
  - setCommitlogArchiver
```
public void setCommitlogArchiver(CommitLogArchiver archiver)
```
  - getActiveSegmentNames
```
public java.util.List<java.lang.String> getActiveSegmentNames()
```
    Specified by:
    
    getActiveSegmentNames in interface CommitLogMBean
    
    Returns:
    
    file names (not full paths) of active commit log segments (segments containing unflushed data)
  - getArchivingSegmentNames
```
public java.util.List<java.lang.String> getArchivingSegmentNames()
```
    Specified by:
    
    getArchivingSegmentNames in interface CommitLogMBean
    
    Returns:
    
    Files which are pending for archival attempt. Does NOT include failed archive attempts.
  - getActiveContentSize
```
public long getActiveContentSize()
```
    Specified by:
    
    getActiveContentSize in interface CommitLogMBean
    
    Returns:
    
    The size of the mutations in all active commit log segments (uncompressed).
  - getActiveOnDiskSize
```
public long getActiveOnDiskSize()
```
    Specified by:
    
    getActiveOnDiskSize in interface CommitLogMBean
    
    Returns:
    
    The space taken on disk by the commit log (compressed).
  - getActiveSegmentCompressionRatios
```
public java.util.Map<java.lang.String,java.lang.Double> getActiveSegmentCompressionRatios()
```
    Specified by:
    
    getActiveSegmentCompressionRatios in interface CommitLogMBean
    
    Returns:
    
    A map between active log segments and the compression ratio achieved for each.
  - shutdownBlocking
```
public void shutdownBlocking()
                      throws java.lang.InterruptedException
```
    Shuts down the threads used by the commit log, blocking until completion. TODO this should accept a timeout, and throw TimeoutException
    
    Throws:
    
    java.lang.InterruptedException
  - resetUnsafe
```
public int resetUnsafe(boolean deleteSegments)
                throws java.io.IOException
```
    FOR TESTING PURPOSES
    
    Returns:
    
    the number of files recovered
    
    Throws:
    
    java.io.IOException
  - resetConfiguration
```
public void resetConfiguration()
```
    FOR TESTING PURPOSES.
  - stopUnsafe
```
public void stopUnsafe(boolean deleteSegments)
```
    FOR TESTING PURPOSES
  - restartUnsafe
```
public int restartUnsafe()
                  throws java.io.IOException
```
    FOR TESTING PURPOSES
    
    Throws:
    
    java.io.IOException
  - freeDiskSpace
```
public static long freeDiskSpace()
```
  - handleCommitError
```
public static boolean handleCommitError(java.lang.String message,
                                        java.lang.Throwable t)
```

Class CommitLog

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

instance

segmentManager

archiver

metrics

Method Detail

start

isStarted

hasFilesToReplay

getUnmanagedFiles

recoverSegmentsOnDisk

recoverFiles

recoverPath

recover

getCurrentPosition

forceRecycleAllSegments

forceRecycleAllSegments

sync

requestExtraSync

add

discardCompletedSegments

getArchiveCommand

getRestoreCommand

getRestoreDirectories

getRestorePointInTime

getRestorePrecision

setCommitlogArchiver

getActiveSegmentNames

getArchivingSegmentNames

getActiveContentSize

getActiveOnDiskSize

getActiveSegmentCompressionRatios

shutdownBlocking

resetUnsafe

resetConfiguration

stopUnsafe

restartUnsafe

freeDiskSpace

handleCommitError