If there really is a difference between SunJDK and OpenJDK on the same system, it could be a bug in OpenJDK that has been fixed in SunJDK.
Oracle tries to apply bug fixes to OpenJDK, but it takes time. It might be useful to look at JDK bug parade. As Kirk stated, the code between OpenJDK and SunJDK is basically the same minus any bug fixes that haven't been applied to openJDK. On Wed, Dec 14, 2011 at 9:23 AM, Kirk <[email protected]> wrote: > +1, these results run counter to my experience. plus, the code used in Linux > is same as that used in Windows. The only difference is with LInux, if there > is a high resolution timer, it will use it. There is no option in Windows. My > experience in the differences between Windows and Linux is that Window 7 > thread scheduling is better than it is in Linux and *much* better than it is > in Windows XP. Since JMeter uses loads of threads I suspect that JMeter puts > extra stress on the thread scheduler. > > One last point, Higher loads equates to more timings from more threads so > IMHO, your observation is some what spurious. > > w.r.t Sun JVM and OpenJDK. The source code for Sun's JDK was the open sourced > to form the OpenJDK. There is no difference in the code base between Sun JDK > and OpenJDK. I'm not sure why you're results got worse as you moved to > OpenJDK. I can only say that most of the time there should be a performance > win as you move to newer versions of the JDK but sometimes I see a > performance loss. It just depends on what your application is sensitive to > what has been changed. > > Regards, > Kirk > > On Dec 14, 2011, at 2:59 PM, Deepak Goel wrote: > >> @Peter >> >> can you please combine your two mails and restate what you are trying >> to point out. Seems they mean different things: >> >> ---------------------- >> Getting currentTimeMillis and nano time has a higher overhead on "linux >> versus windows" >> >> The difference between using currentTimeMillis versus nano time is >> about 20-30% overhead "regardless of the operating system" or version of >> JVM. >> ---------------------- >> >> Also can you please mention exactly what hardware have you measured >> your results for? >> >> On 12/14/11, Peter Lin <[email protected]> wrote: >>> I'll add a little bit more. >>> >>> The difference between using currentTimeMillis versus nano time is >>> about 20-30% overhead regardless of the operating system or version of >>> JVM. >>> >>> I've seen this first hand with Sun, IBM and JRockit on windows and linux. >>> >>> OpenJDK is mostly the same as SunJDK, so there's very little >>> difference from a performance perspective. the SunJDK usually doesn't >>> include the experimental stuff that OpenJDK might have. >>> >>> On Wed, Dec 14, 2011 at 7:41 AM, Deepak Goel <[email protected]> wrote: >>>> Hey >>>> >>>> Looking at your configuration, here is a possible theory... >>>> >>>> Sun Microsystem (Sun JDK) was eaten by Oracle which runs on WINTEL >>>> platforms so the performance of SUN JDK is optimized on INTEL >>>> platforms. OpenJDK is meant for Linux platforms a late entry for INTEL >>>> into this game and hence low performance and high CPU peaks... >>>> >>>> Deepak >>>> >>>> On 12/14/11, Toni Menendez Lopez <[email protected]> wrote: >>>>> My loadserver is running in this server, >>>>> >>>>> Hardware : >>>>> >>>>> Proliant BL460C G1 >>>>> 2xIntel Xeon @2,53Ghz (quad) >>>>> 32 GB of memory >>>>> >>>>> O.S : >>>>> RHEL5.4(Tikanga) >>>>> >>>>> I don´t have stats about that but I will collect in few days that I >>>>> will have again the server available, but my impression is that JMeter >>>>> is taking much more CPU with OpenJDK and is doing lots of big peaks, >>>>> seems problems with GC. >>>>> >>>>> But I will analyze it later, when my actual testing finished. >>>>> >>>>> Toni. >>>>> >>>>> >>>>> 2011/12/13, Deepak Goel <[email protected]>: >>>>>> Hey >>>>>> >>>>>> Looks like an evolution and quality problem..Sun JDK more evolved v/s >>>>>> OpenJDK >>>>>> >>>>>> What is the hardware? What is the performance difference? Stats >>>>>> please... >>>>>> >>>>>> Deepak >>>>>> >>>>>> On 12/13/11, Toni Menendez Lopez <[email protected]> wrote: >>>>>>> Hello all, >>>>>>> >>>>>>> I want to ask all of you on question ! >>>>>>> >>>>>>> I am normally working with SunJDK for Jmeter and running in non-gui >>>>>>> mode, but now I want to migrate the openJDK ( OpenJDK 64-Bit Server VM >>>>>>> (build 1.6.0-b09, mixed mode)). >>>>>>> >>>>>>> I have executed the same test in SunJDK and OpenJDK and I have >>>>>>> experienced that Jmeter has worst performance sending the traffic with >>>>>>> OPenJDK that with SunJDK. >>>>>>> >>>>>>> Any of you have got some similar experience ? >>>>>>> >>>>>>> My O.S is RHEL5.4 >>>>>>> >>>>>>> Best regards, >>>>>>> >>>>>>> Toni. >>>>>>> >>>>>>> --------------------------------------------------------------------- >>>>>>> To unsubscribe, e-mail: [email protected] >>>>>>> For additional commands, e-mail: [email protected] >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Namaskara~Nalama~Guten Tag~Bonjour >>>>>> >>>>>> >>>>>> -- >>>>>> Keigu >>>>>> >>>>>> Deepak >>>>>> +91-9765089593 >>>>>> [email protected] >>>>>> http://www.simtree.net >>>>>> >>>>>> Skype: thumsupdeicool >>>>>> Google talk: deicool >>>>>> Blog: http://loveandfearless.wordpress.com >>>>>> Facebook: http://www.facebook.com/deicool >>>>>> >>>>>> "Contribute to the world, environment and more : >>>>>> http://www.gridrepublic.org >>>>>> " >>>>>> >>>>>> --------------------------------------------------------------------- >>>>>> To unsubscribe, e-mail: [email protected] >>>>>> For additional commands, e-mail: [email protected] >>>>>> >>>>>> >>>>> >>>>> --------------------------------------------------------------------- >>>>> To unsubscribe, e-mail: [email protected] >>>>> For additional commands, e-mail: [email protected] >>>>> >>>>> >>>> >>>> >>>> -- >>>> Namaskara~Nalama~Guten Tag~Bonjour >>>> >>>> >>>> -- >>>> Keigu >>>> >>>> Deepak >>>> +91-9765089593 >>>> [email protected] >>>> http://www.simtree.net >>>> >>>> Skype: thumsupdeicool >>>> Google talk: deicool >>>> Blog: http://loveandfearless.wordpress.com >>>> Facebook: http://www.facebook.com/deicool >>>> >>>> "Contribute to the world, environment and more : >>>> http://www.gridrepublic.org >>>> " >>>> >>>> --------------------------------------------------------------------- >>>> To unsubscribe, e-mail: [email protected] >>>> For additional commands, e-mail: [email protected] >>>> >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: [email protected] >>> For additional commands, e-mail: [email protected] >>> >>> >> >> >> -- >> Namaskara~Nalama~Guten Tag~Bonjour >> >> >> -- >> Keigu >> >> Deepak >> +91-9765089593 >> [email protected] >> http://www.simtree.net >> >> Skype: thumsupdeicool >> Google talk: deicool >> Blog: http://loveandfearless.wordpress.com >> Facebook: http://www.facebook.com/deicool >> >> "Contribute to the world, environment and more : http://www.gridrepublic.org >> " >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [email protected] >> For additional commands, e-mail: [email protected] >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
