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https://issues.apache.org/jira/browse/LOG4J2-1883?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15976645#comment-15976645
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Anthony Maire commented on LOG4J2-1883:
---------------------------------------
Concerning the java.time.Instant allocation, I made a JMH test with JDK
1.8.0_171, and as I suspected, the allocation is removed because of escape
analysis.
Here is the body of the method under test :
{code}
@Benchmark
public long updateTimeStamp(CustomTimestamp timestamp){
Instant now = clock.instant();
timestamp.secondsFromEpoch = now.getEpochSecond();
timestamp.nanoSeconds = now.getNano();
return timestamp.nanoSeconds + timestamp.secondsFromEpoch;
}
{code}
where clock is initialized by java.time.clock.systemUTC()
JMH built in gc profiler reported less than 1 byte allocated by benchmark
iteration (which is probably caused by JMH itself)
I double checked with Java Mission Control, and no Instant was allocated during
a 15 min run.
JMH returned a 20ns average time, so the code should be not eliminated by the
JIT compiler.
Another test should be done on Java 9, since the clock.instant() method is a
little more complex and maybe the escape analysis doesn't work there, but at
first sight, it seems than the allocation issue can be avoided.
However I don't know if relying on escape analysis is an acceptable way of
conform with the 0-allocation policy, since it is VM dependant.
> Timestamp does not seem to support microseconds level
> -----------------------------------------------------
>
> Key: LOG4J2-1883
> URL: https://issues.apache.org/jira/browse/LOG4J2-1883
> Project: Log4j 2
> Issue Type: Bug
> Components: Configurators
> Environment: Linux with any JDK including JDK1.8
> Reporter: Madhava Dass
> Priority: Critical
>
> Used log4j and 'log4j2.xml' to configure timestamp format as:
> {code}
> <?xml version="1.0" encoding="UTF-8"?>
> <Configuration status="WARN">
> <Appenders>
> <Console name="Console" target="SYSTEM_OUT">
> <PatternLayout
> pattern="[%d{yyyy-MM-dd'T'HH:mm:ss.SSSXXX}{UTC}][%level][%logger{36}]:%msg%n"/>
> </Console>
> </Appenders>
> <Loggers>
> <Root level="DEBUG">
> <AppenderRef ref="Console"/>
> </Root>
> </Loggers>
> </Configuration>
> {code}
> This pattern produces the time stamp as:
> {code}
> [2017-03-29T13:55:28.363000][null]:[Thread-1]: - <message>
> {code}
> The desired output is:
> {code}
> [2017-03-29T13:55:28.363701-07:00][null]:[Thread-1]: - <message>
> {code}
> Different versions of JDKs were tried including JDK 1.8. It does not seem to
> make any difference in the outcome.
> Is there a way to get the desired time stamp through pattern matching
> configuration in the '*.xml' file?
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