Can you change the configuration to start with <Configuration status="trace"
and verify that the correct configuration file (with includeLocation="false") is in use? I suspect there is something wrong because this change should make a large difference in performance. Sent from my iPhone > On 2015/10/12, at 15:22, Strong Su <lovelo...@gmail.com> wrote: > > Hi Remko. Thanks for the reply. > I changed includeLocation to false and re-run the test. > But it didn't change better. QPS is still about 5000. > > I found user occupies CPU for about 70% when I run sync log4j1 and sync > log4j2. > But when I run async log4j2, it's only about 30% and system occupies for > about 70%. > All of them(include sync log4j2 and async log4j2) are under very high load > average. > Are these normal numbers? > >> On Sun, Oct 11, 2015 at 7:56 PM, Remko Popma <remko.po...@gmail.com> wrote: >> >> See also http://logging.apache.org/log4j/2.x/manual/async.html#Location >> and >> >> http://logging.apache.org/log4j/2.x/manual/async.html#Throughput_of_Logging_With_Location_includeLocationtrue >> >> On Sun, Oct 11, 2015 at 1:54 PM, Remko Popma <remko.po...@gmail.com> >> wrote: >> >>> The problem with the strange performance result is because of the >>> configuration: >>> You have includeLocation=true. This will force Log4j to take a snapshot >> of >>> the stack and is very slow. >>> >>> Your layouts do not actually use this information, and this explains why >>> synchronous logging is faster: synchronous logging will _only_ take a >>> snapshot of the stack when the layout needs it. In your case this is >> never, >>> so you get fast performance. >>> >>> The solution is to change your config to >>> <Root level="info" includeLocation="false"> >>> >>> If you test this with async loggers you should see a performance >>> improvement immediately. >>> >>>> On Sun, Oct 11, 2015 at 12:21 PM, Strong Su <lovelo...@gmail.com> wrote: >>>> >>>> My log4j2 sync configuration is: >>>> >>>> <?xml version="1.0" encoding="UTF-8"?> >>>> <Configuration> >>>> <Appenders> >>>> <!-- Async Loggers will auto-flush in batches, so switch off >>>> immediateFlush. --> >>>> <File name="File" fileName="{PATH}/a.log" >>>> immediateFlush="false" append="false"> >>>> <PatternLayout pattern="%d %-5p [%c{2}] %m%n"/> >>>> </File> >>>> <Console name="STDOUT" target="SYSTEM_OUT"> >>>> <PatternLayout pattern="%d %-5p [%c{2}] %m%n"/> >>>> </Console> >>>> </Appenders> >>>> >>>> <Loggers> >>>> <Root level="info" includeLocation="true"> >>>> <AppenderRef ref="File"/> >>>> <AppenderRef ref="STDOUT"/> >>>> </Root> >>>> </Loggers> >>>> >>>> </Configuration> >>>> >>>> And async configuration change <Root> to <AsyncRoot> >>>> >>>> On Sun, Oct 11, 2015 at 10:51 AM, Remko Popma <remko.po...@gmail.com> >>>> wrote: >>>> >>>>> Can you post your log4j2 configuration? >>>>> >>>>> Sent from my iPhone >>>>> >>>>>> On 2015/10/10, at 21:58, Strong Su <lovelo...@gmail.com> wrote: >>>>>> >>>>>> I insert a log in a http request function on server side. And I >> start >>>>>> requests continually on client side through hundreds of threads. >>>>>> I measure the performance through QPS because server has to print a >>>> log >>>>>> whenever it receive a request. The time delayed by logging will >>>> influence >>>>>> QPS heavily. >>>>>> When I didn't insert a log in the request function, QPS was about >>>> 20000. >>>>>> When I inserted a log4j1 log, QPS was about 10000. >>>>>> When I inserted a log4j2 sync log, QPS was about 18000. >>>>>> But when I inserted a log4j2 asycn log, QPS was only about 5000. >>>>>> >>>>>>> On Sat, Oct 10, 2015 at 8:34 PM, Remko Popma < >> remko.po...@gmail.com> >>>>> wrote: >>>>>>> >>>>>>> How did you measure the good performance (with sync logging) and >> the >>>> bad >>>>>>> performance (with async)? What happens exactly when "it turns >>>> terrible"? >>>>>>> >>>>>>>> On Saturday, 10 October 2015, Strong Su <lovelo...@gmail.com> >>>> wrote: >>>>>>>> >>>>>>>> Hello everyone, >>>>>>>> I'm still testing log4j2 on our projects. >>>>>>>> When using it, I find it has a beautiful performance when using >> sync >>>>>>>> log4j2. >>>>>>>> But it turns terrible when I add -DLog4jContextSelector or change >>>>> <root> >>>>>>> to >>>>>>>> <AsyncRoot> in log4j2.xml to use async log4j2. >>>>>>>> I don't even have a clue on explaining this.What could cause this >>>>> bizarre >>>>>>>> problem? >>>>>>>> >>>>>>>> Thank you. >>>>>>>> Best regards, >>>>>>>> Dylan Su >>>>>>> >>>>> >>>>> --------------------------------------------------------------------- >>>>> To unsubscribe, e-mail: log4j-user-unsubscr...@logging.apache.org >>>>> For additional commands, e-mail: log4j-user-h...@logging.apache.org >>>>> >>>>> >>>> >>> >>> >> --------------------------------------------------------------------- To unsubscribe, e-mail: log4j-user-unsubscr...@logging.apache.org For additional commands, e-mail: log4j-user-h...@logging.apache.org
