MetricsWAL (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.regionserver.wal.WALActionsListener.Base
- - org.apache.hadoop.hbase.regionserver.wal.MetricsWAL

All Implemented Interfaces:

WALActionsListener
```
@InterfaceAudience.Private
public class MetricsWAL
extends WALActionsListener.Base
```
Class used to push numbers about the WAL into the metrics subsystem. This will take a single function call and turn it into multiple manipulations of the hadoop metrics system.

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.regionserver.wal.WALActionsListener
  WALActionsListener.Base

Field Summary

Fields
Modifier and Type Field and Description

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

private MetricsWALSource source

Fields
Modifier and Type	Field and Description
`private static org.apache.commons.logging.Log`	`LOG`
`private MetricsWALSource`	`source`

Constructor Summary

Constructors
Constructor and Description

MetricsWAL()

MetricsWAL(MetricsWALSource s)

Constructors
Constructor and Description
`MetricsWAL()`
`MetricsWAL(MetricsWALSource s)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`logRollRequested(boolean underReplicated)` A request was made that the WAL be rolled.
`void`	`postAppend(long size, long time)` For notification post append to the writer.
`void`	`postSync(long timeInNanos, int handlerSyncs)` For notification post writer sync.

Methods inherited from class org.apache.hadoop.hbase.regionserver.wal.WALActionsListener.Base
logCloseRequested, postLogArchive, postLogRoll, preLogArchive, preLogRoll, visitLogEntryBeforeWrite, visitLogEntryBeforeWrite

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
```
  - source
```
private final MetricsWALSource source
```
- Constructor Detail
  - MetricsWAL
```
public MetricsWAL()
```
  - MetricsWAL
```
MetricsWAL(MetricsWALSource s)
```
- Method Detail
  - postSync
```
public void postSync(long timeInNanos,
            int handlerSyncs)
```
    Description copied from interface: WALActionsListener
    
    For notification post writer sync. Used by metrics system at least.
    
    Specified by:
    
    postSync in interface WALActionsListener
    
    Overrides:
    
    postSync in class WALActionsListener.Base
    
    Parameters:
    timeInNanos - How long the filesystem sync took in nanoseconds.
    handlerSyncs - How many sync handler calls were released by this call to filesystem sync.
  - postAppend
```
public void postAppend(long size,
              long time)
```
    Description copied from interface: WALActionsListener
    
    For notification post append to the writer. Used by metrics system at least. TODO: Combine this with above.
    
    Specified by:
    
    postAppend in interface WALActionsListener
    
    Overrides:
    
    postAppend in class WALActionsListener.Base
    
    Parameters:
    size - approx length of cells in this append.
    time - elapsed time in milliseconds.
  - logRollRequested
```
public void logRollRequested(boolean underReplicated)
```
    Description copied from interface: WALActionsListener
    
    A request was made that the WAL be rolled.
    
    Specified by:
    
    logRollRequested in interface WALActionsListener
    
    Overrides:
    
    logRollRequested in class WALActionsListener.Base

Class MetricsWAL

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.regionserver.wal.WALActionsListener

Field Summary

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.regionserver.wal.WALActionsListener.Base

Methods inherited from class java.lang.Object

Field Detail

LOG

source

Constructor Detail

MetricsWAL

MetricsWAL

Method Detail

postSync

postAppend

logRollRequested