[
https://issues.apache.org/jira/browse/LOG4J2-354?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15601438#comment-15601438
]
Pawel Rein commented on LOG4J2-354:
-----------------------------------
Thank you for bringing the issue up and for explanations.
I'd like to just confirm, from tests / observations in my environment, that
using *copytruncate does not help*.
> log4j2 + FastFileAppender + Tomcat logrotate problem
> ----------------------------------------------------
>
> Key: LOG4J2-354
> URL: https://issues.apache.org/jira/browse/LOG4J2-354
> Project: Log4j 2
> Issue Type: Bug
> Affects Versions: 2.0-beta8
> Environment: log4j2-beta8
> disruptor 3.1.1
> tomcat 7 with Java 1.6
> We use the SLF4J library as well.
> Reporter: Remko Popma
>
> (from log4j-user mailing list)
> Kamil Mroczek wrote:
> Hello,
> We decided to try out log4j2-beta8 to see if we could improve our logging
> performance. We were testing with the disruptor 3.1.1. library to make all
> our appenders async.
> {{-DLog4jContextSelector=org.apache.logging.log4j.core.async.AsyncLoggerContextSelector}}
> We are running tomcat 7 with Java 1.6. We use the SLF4J library as well.
> The appender that we were using in this case was the Fast File Appender with
> a definition like:
> {code}
> <FastFile name="RequestLog" fileName="requests.log"
> immediateFlush="false" append="true">
> <PatternLayout>
> <pattern>%m%n</pattern>
> </PatternLayout>
> </FastFile>
> {code}
> And logger was..
> {code}
> <logger name="a.namespace" level="info" additivity="false">
> <appender-ref ref="RequestLog"/>
> </logger>
> {code}
> So the system was designed to allow log4j to do the logging and then have
> logrotate rotate the log files from the host to an external destination.
> We rotate the logs every 5 minutes with these params (with LZO compression).
> compress
> compresscmd /bin/lzop
> compressoptions "-U"
> compressext .lzo
> What we were seeing was that after a log rotation happened the new file would
> start with a massive chunk of binary data at the start. Many times on the
> order of 100-200MB. This would turn the logs from being on the order of
> 50-100MB to 200-350MB.
> My guess was that it had something to do with the byte buffer flushing
> mid-rotate since these chunks always come at the start of the file. But I
> also saw LOG4J2-295 (Fast(Rolling)FileAppender now correctly handles messages
> exceeding the buffer size. ) which was fixed in beta8 which my discredit that
> idea.
> We were able to fix the issue by using the regular FileAppender like this:
> {code}
> <File name="RequestLog" fileName="requests.log" immediateFlush="true"
> append="true" bufferedIO="false">
> <PatternLayout>
> <pattern>%m%n</pattern>
> </PatternLayout>
> </File>
> {code}
> I can't remember for certain, but I am pretty sure that even if we had
> bufferedIO="true" on the FileAppender everything worked okay as well.
> We could reproduce it pretty consistently. I wanted to post to the group to
> see if anyone has seen anything like this before. Any ideas on what the
> issue could be?
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: log4j-dev-unsubscr...@logging.apache.org
For additional commands, e-mail: log4j-dev-h...@logging.apache.org
