logging-log4j-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Mariano Gonzalez (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (LOG4J2-927) Race condition between a LoggerContext stop() and async loggers
Date Thu, 28 May 2015 19:25:19 GMT

    [ https://issues.apache.org/jira/browse/LOG4J2-927?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14563528#comment-14563528

Mariano Gonzalez commented on LOG4J2-927:

still happens in 2.3.. Something I saw in 2.1, is that not all loggers are stopped. In org.apache.logging.log4j.core.config.AbstractConfiguration#stop:251
loggers are not stopped if they're already on a set. However, because the hashCode is based
on the state and not the instance itself, only the first logger is stopped and the rest are
wrongfully considered as stopped.

However, this alone doesn't seem to be enough to fix the issue

> Race condition between a LoggerContext stop() and async loggers
> ---------------------------------------------------------------
>                 Key: LOG4J2-927
>                 URL: https://issues.apache.org/jira/browse/LOG4J2-927
>             Project: Log4j 2
>          Issue Type: Bug
>          Components: Appenders
>    Affects Versions: 2.1
>            Reporter: Mariano Gonzalez
> I have an application in which I'm using all async loggers. When I stop the LoggerContext,
there're still some events waiting in disruptor's buffer and when it tries to execute them
the context is already closed and thus those events are lost. In the case of a RollingFileAppender,
I get an IOException because the outputStream has already been closed.
> As a debugging technique, I did an Appedder decorator that looks like this:
> {code:java}
> final class StopConditionSafeAppenderWrapper extends BaseAppenderWrapper
> {
>     private final LoggerContext loggerContext;
>     StopConditionSafeAppenderWrapper(Appender delegate, LoggerContext loggerContext)
>     {
>         super(delegate);
>         this.loggerContext = loggerContext;
>     }
>     @Override
>     public void append(LogEvent event)
>     {
>         if (!loggerContext.isStarted()) {
>              return;
>         }
>         super.append(event);
>     }
> }
> {code}
> With the help of a debugger, I could verify that when the append method was invoked the
loggerContext was started but then by the time the exception occurred it was closed.
> It checked the code at LoggerContext#stop() and saw that there's code to prevent disruptor
from taking new events once a stop() has been invoked, but there's no code to wait for the
ring buffer to be fully consumed before actually stopping.

This message was sent by Atlassian JIRA

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

View raw message