Package com.tangosol.io.journal

Class FlashJournalRM.WriterDaemon.PendingWriteTask

java.lang.Object

com.tangosol.io.journal.FlashJournalRM.WriterDaemon.PendingWriteTask

All Implemented Interfaces:

Runnable

Enclosing class:

FlashJournalRM.WriterDaemon

protected class FlashJournalRM.WriterDaemon.PendingWriteTask
extends Object
implements Runnable

A task that gets queued to perform an asynchronous appending write on the WriterDaemon thread.

Constructor Summary

Constructors

Constructor	Description
PendingWriteTask(FlashJournalRM.JournalFile jrnlfile, FlashJournalRM.Buffer buf, int cbBuffer)	Construct a PendingWriteInfo "struct".

Method Summary

Modifier and Type	Method	Description
protected void	processWriteException(IOException ioe, List<FlashJournalRM.Buffer> listBuffer, ByteBuffer[] aniobuf, FlashJournalRM.JournalFile jrnlfile)	Process IOException while flushing the buffers to disk.
void	run()	Execute the task, writing the buffer to the end of the file.
protected void	writeRemainder(IOException e, List<FlashJournalRM.Buffer> listBuffer, ByteBuffer[] aniobuf, boolean fSingleBlockWrite)	Write what has not been written (remainder) to disk.
protected boolean	writeToFile(FlashJournalRM.JournalFile jrnlfile, ByteBuffer[] aniobuf, List listBuffer, int cb)	Write the provided buffers to the FlashJournalRM.JournalFile.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PendingWriteTask

public PendingWriteTask(FlashJournalRM.JournalFile jrnlfile,
                        FlashJournalRM.Buffer buf,
                        int cbBuffer)

Construct a PendingWriteInfo "struct".

Parameters:

jrnlfile - the file to append to

buf - the buffer to append

cbBuffer - the number of bytes to append from the buffer

Method Detail

run

public void run()

Execute the task, writing the buffer to the end of the file.

Specified by:

run in interface Runnable

writeToFile

protected boolean writeToFile(FlashJournalRM.JournalFile jrnlfile,
                              ByteBuffer[] aniobuf,
                              List listBuffer,
                              int cb)

Write the provided buffers to the FlashJournalRM.JournalFile. This method will reattempt writes if writes fully or partially fail via processWriteException(java.io.IOException, java.util.List<com.tangosol.io.journal.FlashJournalRM.Buffer>, java.nio.ByteBuffer[], com.tangosol.io.journal.FlashJournalRM.JournalFile).

Parameters:

jrnlfile - the JournalFile the buffers should be written to

aniobuf - the NIO byte buffers to persist

listBuffer - the buffers maintained by the buffer pool

cb - the number of bytes to write

Returns:

true if the buffers where successfully written

processWriteException

protected void processWriteException(IOException ioe,
                                     List<FlashJournalRM.Buffer> listBuffer,
                                     ByteBuffer[] aniobuf,
                                     FlashJournalRM.JournalFile jrnlfile)

Process IOException while flushing the buffers to disk.

Upon encountering a write exception the write is reattempted with an increasing interval between attempts. This method switches the FlashJournalRM.CongestionPolicy allowing exceptions to be thrown to the client as the Journal naturally enters congestion.

Control may be returned to the caller with the Journal being unable to be repaired; this is highlighted by the throwing of a RuntimeException or the current thread's interrupt bit being set. In the latter case the Journal may wish to operate in a read-only mode.

Parameters:

ioe - the IOException

listBuffer - the list of buffers to be flushed to disk

aniobuf - the array of byte buffers to be flushed to disk

jrnlfile - the FlashJournalRM.JournalFile being written from

Throws:

IllegalStateException - if the write could not be completed / repaired

writeRemainder

protected void writeRemainder(IOException e,
                              List<FlashJournalRM.Buffer> listBuffer,
                              ByteBuffer[] aniobuf,
                              boolean fSingleBlockWrite)
                       throws IOException

Write what has not been written (remainder) to disk. The remainder is derived based on current-buffers - bytes-written-to-file. This method is invoked as a result of some raw (device) error thus the exception argument. This ensures we do not lose the initial cause as we replay writes.

Parameters:

e - the IOException

listBuffer - the list of buffers to be flushed to disk

aniobuf - the array of byte buffers to be flushed to disk

fSingleBlockWrite - whether to switch the preference in favor of single block writes

Throws:

IOException