[
https://issues.apache.org/jira/browse/LOG4J2-1121?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14791378#comment-14791378
]
Remko Popma commented on LOG4J2-1121:
-------------------------------------
It may be possible to fix the race condition in the counter/waitForCompletion
design by incrementing the counter before calling LoggerConfig.log:
{code}
// Logger, similar change needed in AsyncLogger
public void logMessage(final String fqcn, final Level level, final Marker
marker,
final Message message, final Throwable t) {
final Message msg = message == null ? new SimpleMessage(Strings.EMPTY) :
message;
config.config.getConfigurationMonitor().checkConfiguration();
// The above line may trigger a reconfig, so load volatile field again.
// Subtle point: hoist volatile field into local var, since we will use it
twice.
LoggerConfig loggerConfig = privateConfig.loggerConfig;
// increment counter first
loggerConfig.beforeLog();
// then call log method
loggerConfig.log(getName(), fqcn, marker, level, msg, t);
{code}
Then of course we need to fix AbstractConfiguration to call clearAppenders
before it stops the Appenders.
I think this should work (prevent log events getting dropped with a reconfig).
What I don't like though is how this mechanism is spread out over several
classes and depends on all participants doing the right thing in the right
order...
> LoggerConfig performance improvement: remove waitForCompletion and associated
> fields
> ------------------------------------------------------------------------------------
>
> Key: LOG4J2-1121
> URL: https://issues.apache.org/jira/browse/LOG4J2-1121
> Project: Log4j 2
> Issue Type: Improvement
> Components: Core
> Affects Versions: 2.3
> Reporter: Remko Popma
>
> This ticket follows up on LOG4J2-1120. Out of the three changes identified in
> LOG4J2-1120, only two could be implemented in time for the 2.4 release.
> This ticket tracks the remaining work for the third change:
> * Since {{clearAppenders()}} is only called after all appenders have been
> stopped, {{waitForCompletion()}} may no longer be necessary (unless I am
> missing something here). If so, the {{shutdownLock}}, {{shutdown}} and
> {{counter}} fields can be removed. Not incrementing the atomic counters with
> every event in the hot path should give better performance.
> LOG4J2-1120 shows benchmark results that support this.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
