org.apache.cassandra.utils.binlog

Class BinLog

java.lang.Object

org.apache.cassandra.utils.binlog.BinLog

All Implemented Interfaces:

java.lang.Runnable

public class BinLog
extends java.lang.Object
implements java.lang.Runnable

Bin log is a is quick and dirty binary log that is kind of a NIH version of binary logging with a traditional logging framework. It's goal is good enough performance, predictable footprint, simplicity in terms of implementation and configuration and most importantly minimal impact on producers of log records. Performance safety is accomplished by feeding items to the binary log using a weighted queue and dropping records if the binary log falls sufficiently far behind. Simplicity and good enough perforamance is achieved by using a single log writing thread as well as Chronicle Queue to handle writing the log, making it available for readers, as well as log rolling.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BinLog.Builder
static class	BinLog.ReleaseableWriteMarshallable

Field Summary

Fields

Modifier and Type	Field and Description
java.nio.file.Path	path
static java.lang.String	TYPE
static java.lang.String	VERSION

Method Summary

Modifier and Type	Method and Description
static java.lang.Throwable	cleanDirectory(java.io.File directory, java.lang.Throwable accumulate)
void	finalize() There is a race where we might not release a buffer, going to let finalization catch it since it shouldn't happen to a lot of buffers.
BinLogOptions	getBinLogOptions()
void	logRecord(BinLog.ReleaseableWriteMarshallable record)
boolean	offer(BinLog.ReleaseableWriteMarshallable record) Offer a record to the log.
void	put(BinLog.ReleaseableWriteMarshallable record) Put a record into the log.
void	run()
void	stop() Stop the consumer thread that writes log records.

Methods inherited from class java.lang.Object

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

Field Detail

path

public final java.nio.file.Path path

VERSION

public static final java.lang.String VERSION

See Also:

Constant Field Values

TYPE

public static final java.lang.String TYPE

See Also:

Constant Field Values

Method Detail

getBinLogOptions

public BinLogOptions getBinLogOptions()

stop

public void stop()
          throws java.lang.InterruptedException

Stop the consumer thread that writes log records. Can be called multiple times.

Throws:

java.lang.InterruptedException

offer

public boolean offer(BinLog.ReleaseableWriteMarshallable record)

Offer a record to the log. If the in memory queue is full the record will be dropped and offer will return false.

Parameters:

record - The record to write to the log

Returns:

true if the record was queued and false otherwise

put

public void put(BinLog.ReleaseableWriteMarshallable record)
         throws java.lang.InterruptedException

Put a record into the log. If the in memory queue is full the putting thread will be blocked until there is space or it is interrupted.

Parameters:

record - The record to write to the log

Throws:

java.lang.InterruptedException

run

public void run()

Specified by:

run in interface java.lang.Runnable

finalize

public void finalize()

There is a race where we might not release a buffer, going to let finalization catch it since it shouldn't happen to a lot of buffers. Only test code would run into it anyways.

Overrides:

finalize in class java.lang.Object

logRecord

public void logRecord(BinLog.ReleaseableWriteMarshallable record)

cleanDirectory

public static java.lang.Throwable cleanDirectory(java.io.File directory,
                                                 java.lang.Throwable accumulate)