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

Nicolas Carranza nicarran at gmail.com
Sun Apr 22 23:06:03 PDT 2012

hi Anthony,

The little patch against the current http://hg.openjdk.java.net/jdk8/jdk8/jdk repo is attached. Running: time -f '%P' java PerformanceRegressionTest2 useLogging 3 times using the (JRE 1.7.0_03-b04 + escapeDoLog.patch) gives the following CPU usages: 14%, 13%, 13%.

Please let me know if I can be of further help.

Cheers, Nicolas

On 04/18/2012 05:08 AM, Anthony Petrov wrote:

Hi Nicolas,

Frederico's patch is needed - with that patch we avoid string concatenation operations in XAWT code if logging has been disabled. These operations caused heavy memory usage, and eliminating them resolved the issue reported by Frederico. We don't want to revert that patch. In fact, I think that analyzing AWT logging code on other platforms (Windows and Mac) and developing a similar fix for them makes very much sense as well. However, your suggestion is also valid. This is because in cases when we don't build complex strings for logging in AWT code, we don't usually guard such logging statements with if (...loggable...) checks. Your suggested change will address these specific cases, too, by eliminating some internal string building operations in the logger code itself, thus boosting performance even further. Could you prepare a patch please, test it, and send it out for a review? -- best regards, Anthony On 4/18/2012 5:01 AM, Nicolas Carranza wrote: Federico's patch solves the performance regression (see: http://mail.openjdk.java.net/pipermail/jdk7u-dev/2012-April/002694.html ). But instead of this patch I find better to change the PlatformLogger class: insert "if(!isLoggable(level)) return;" at the beginning of the method sun.util.logging.PlatformLogger.JavaLogger.doLog(int level, String msg, Object... params) . The string convertion affecting the performance is done on the PlatformLogger.JavaLogger.doLog (even when the message is not loggable) and it is there where the problem should be fixed (to be more clear and also cover more use cases). Fixing it there also clears why the performance regression does not happen when redirectPlatformLoggers has not been called (when logging is not used): PlatformLogger.LoggerProxy.doLog(int level, String msg, Object... params) does not do the string convertion when the message is not loggable.

Federico's patch has already been pushed to the jdk8 repository, when will it be applied to jdk7 (or my propossed change if it is preferred)? [ Here is a jvisualvm memory profiling snapshot of_ _PerformanceRegresionTest3:_ _http://www.java.net/forum/topic/performance/general-performance-discussion/jre7s-javaawt-performance-degradation-caused-javautillogging-linux#comment-823486 . ] Cheers, 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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