logging-log4j-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Remko Popma (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (LOG4J2-164) Add methods is/setEndOfBatch to LogEvent (buffered appender performance improvement)
Date Mon, 11 Feb 2013 07:03:12 GMT

     [ https://issues.apache.org/jira/browse/LOG4J2-164?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Remko Popma updated LOG4J2-164:
-------------------------------

    Description: 
Many buffered Appenders have an attribute "immediateFlush" that gives users the option to
follow each write with a flush to ensure that all messages are available on disk. The drawback
of the immediateFlush idiom is the performance impact of touching the disk on every single
event.

If the appender could determine from the current LogEvent whether any more events are expected,
it could avoid unnecessary flushes and only write to disk when the last event was received
(or the buffer is full). 

This would work especially nicely when receiving bursts of events - a common scenario - when
you want to avoid adding more overhead to a system that is already very busy.

Asynchronous loggers and appenders are well-positioned to use such a mechanism: they can easily
call LogEvent.setEndOfBatch(true) if the current event is the last one in the queue.

The patches I proposed for LOG4J2-151 and LOG4J2-163 already use this mechanism internally.
The FastFileAppender included in these patches checks if a log event is a specific class,
casts the event to that class, and finally calls the isEndOfBatch method on that event. However
I think the idea is generally applicable to any buffered appender and adding these methods
to the LogEvent interface would benefit users of the existing AsynchAppender and OutputStreamAppender
classes.


  was:
Many buffered Appenders have an attribute "immediateFlush" that gives users the option to
follow each write with a flush to ensure that all messages are available on disk. The drawback
of the immediateFlush idiom is the performance impact of touching the disk on every single
event.

If the appender could determine from the current LogEvent whether any more events are expected,
it could avoid unnecessary flushes and only write to disk when the last event was received
(or the buffer is full). 

This would work especially nicely when receiving bursts of events - a common scenario - when
you want to avoid adding more overhead to a system that is already very busy.

Asynchronous loggers and appenders are well-positioned to use such a mechanism: they can easily
call LogEvent.setEndOfBatch(true) if the current event is the last one in the queue.

The patches I proposed for LOG4J2-151 and LOG4J2-163 already use this mechanism internally
with the FastFileAppender included in these patches, but I think the idea is generally applicable
to any buffered appender.


    
> Add methods is/setEndOfBatch to LogEvent (buffered appender performance improvement)
> ------------------------------------------------------------------------------------
>
>                 Key: LOG4J2-164
>                 URL: https://issues.apache.org/jira/browse/LOG4J2-164
>             Project: Log4j 2
>          Issue Type: Improvement
>          Components: Core
>    Affects Versions: 2.0-beta4
>            Reporter: Remko Popma
>
> Many buffered Appenders have an attribute "immediateFlush" that gives users the option
to follow each write with a flush to ensure that all messages are available on disk. The drawback
of the immediateFlush idiom is the performance impact of touching the disk on every single
event.
> If the appender could determine from the current LogEvent whether any more events are
expected, it could avoid unnecessary flushes and only write to disk when the last event was
received (or the buffer is full). 
> This would work especially nicely when receiving bursts of events - a common scenario
- when you want to avoid adding more overhead to a system that is already very busy.
> Asynchronous loggers and appenders are well-positioned to use such a mechanism: they
can easily call LogEvent.setEndOfBatch(true) if the current event is the last one in the queue.
> The patches I proposed for LOG4J2-151 and LOG4J2-163 already use this mechanism internally.
The FastFileAppender included in these patches checks if a log event is a specific class,
casts the event to that class, and finally calls the isEndOfBatch method on that event. However
I think the idea is generally applicable to any buffered appender and adding these methods
to the LogEvent interface would benefit users of the existing AsynchAppender and OutputStreamAppender
classes.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

---------------------------------------------------------------------
To unsubscribe, e-mail: log4j-dev-unsubscribe@logging.apache.org
For additional commands, e-mail: log4j-dev-help@logging.apache.org


Mime
View raw message