java.awt event processing performance degradation on JRE7 (original) (raw)

Nicolas Carranza nicarran at gmail.com
Tue Apr 17 01:09:30 PDT 2012

java.util.logging.LogManager isn't loaded when running the PerformanceRegressionTest2 without using logging (http://www.java.net/forum/topic/performance/general-performance-discussion/jre7s-javaawt-performance-degradation-caused-javautillogging-linux):

java -verbose:class PerformanceRegressionTest2 | grep LogManager -- nothing on stdout.

But when using logging:

java -verbose:class PerformanceRegressionTest2 useLogging | grep LogManager -- I get on stdout: [Loaded java.util.logging.LogManager from /opt/oracle-jdk-bin-1.7.0.3/jre/lib/rt.jar] ... And the performance degradation is enabled.

When I started searching for the cause this problem I tryed comparing the scenarios by profiling using jvisualvm but I couldn't find any difference. I later discovered that jvisualvm seems to cause to always load the LogManager class on the jvm it is connecting to. jvisualvm was profiling always the scenario of performance degradation:

java -verbose:class PerformanceRegressionTest2 | grep LogManager -- then connecting jvisualvm always causes: [Loaded java.util.logging.LogManager from /opt/oracle-jdk-bin-1.7.0.3/jre/lib/rt.jar] ...

I haven't done any more profiling so far.

By comparing the java.util.logging sources of the JRE6 and JRE7 I noticed the new sun.util.logging.PlatformLogger.redirectPlatformLoggers() call done in LogManager and changed the line 'Logger.getLogger("")' on PerformanceRegressionTest2 to 'sun.util.logging.PlatformLogger.redirectPlatformLoggers()' (as Logger.getLogger calls indirectly redirectPlatformLoggers) and found that it caused the same performance degradation.

Thank you! Nicolas

On 04/16/2012 09:40 PM, Mandy Chung wrote:

Nicolas,

Thanks for reporting the problem. I am curious if you have collected any profiling data that shows sun.util.logging.PlatformLogger.redirectPlatformLoggers() is the cause of the performance degradation. This redirection is done as part of the logging initialization before JFrame is initialized. Since the performance degradation you observed is after the JFrame has been instantiated, it could be something else. If it's logging-related, it would be sun.util.logging.PlatformLogger. Mandy On 4/16/2012 6:18 AM, Daniel D. Daugherty wrote: java.util.logging is currently handled by the Serviceability Team. Adding that alias to this e-mail thread...

Dan

On 4/16/12 12:17 AM, Nicolas Carranza wrote: Moving the mouse pointer over a java.awt.Window using JRE7 consumes aprox. twice the CPU time as with JRE6 when logging is used (when a call to java.util.logging.getLogger(String)---even without using the returned Logger--- has been done). Keyboard key event processing suffers the same performance penalty. For steps to reproduce this problem please look at: http://www.java.net/forum/topic/performance/general-performance-discussion/jre7s-javaawt-performance-degradation-caused-javautillogging-linux . The performance degradation seems to be "enabled" by the call of sun.util.logging.PlatformLogger.redirectPlatformLoggers() done inside java.util.LogManager.readPrimorialConfiguration() on JRE7. Call chain: Logger.getLogger()->LogManager.getLogManager()-> LogManager.readPrimordialConfiguration()->sun.util.logging.PlatformLogger.redirectPlatformLoggers().

This call is not made on JRE6. If this problem is not easy to solve then I guess is better to remove this call from JRE7's readPrimordialConfiguration as it does more harm than good. Please let me know if there is a better place to report this problem. A couple of weeks ago I "opened" a bug report on bugs.sun.com but I received no response at all. Cheers, Nicolas

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