Aye -----Original Message----- From: Andy Allan [mailto:[EMAIL PROTECTED] Sent: 15 April 2005 10:49 To: CF-Talk Subject: Re: sorry, back to JVM/GC for a moment
I've have varying success with the ConcMarkSweep collector, so yup JVM tuning is most definately a black art. On 4/15/05, Robertson-Ravo, Neil (RX) <[EMAIL PROTECTED]> wrote: > We ran an 8 month test on one of our applications (heavy use - high mem > load) and found this type of GC to be bad, very bad - there were on twin > 3ghz Xeon machines. Basically the app would run great for a while but when > it did its GC - which essentially a global GC it would pause the app > stopping connections to JRun - obviously tweaking the JVM is Application > specific *there is no optimum setup or everyone*. > > > -----Original Message----- > From: Andy Allan [mailto:[EMAIL PROTECTED] > Sent: 15 April 2005 09:38 > To: CF-Talk > Subject: Re: sorry, back to JVM/GC for a moment > > Mmmm, I need to read to emails more closely... :) > > This collector CAN be used on multiple CPU machines and just to quote > the Sun JVM docs (as I can't be botherd rehashing it myself) > > "Use the concurrent low pause collector if your application would > benefit from shorter garbage collector pauses and can afford to share > processor resources with the garbage collector when the application is > running. Typically applications which have a relatively large set of > long-lived data (a large tenured generation), and run on machines with > two or more processors tend to benefit from the use of this collector. > However, this collector should be considered for any application with > a low pause time requirement. Optimal results have been observed for > interactive applications with tenured generations of a modest size on > a single processor." > > Andy > > On 4/15/05, Andy Allan <[EMAIL PROTECTED]> wrote: > > -XX:+UseConcMarkSweep can be used successfully on single CPU machines. > > > > This collector cleans up the tenured generation in parallel with the > > execution of the application but it doesn't actually require multiple > > CPUs (although it will of course benefit from 2+ CPUs) > > > > Andy > > > > On 4/15/05, Robertson-Ravo, Neil (RX) > > <[EMAIL PROTECTED]> wrote: > > > This -XX:+UseConcMarkSweepGC should not be used on a dual processor box. > You > > > can remove it altogether to get better 0performance. This e-mail is from Reed Exhibitions (Oriel House, 26 The Quadrant, Richmond, Surrey, TW9 1DL, United Kingdom), a division of Reed Business, Registered in England, Number 678540. It contains information which is confidential and may also be privileged. It is for the exclusive use of the intended recipient(s). If you are not the intended recipient(s) please note that any form of distribution, copying or use of this communication or the information in it is strictly prohibited and may be unlawful. If you have received this communication in error please return it to the sender or call our switchboard on +44 (0) 20 89107910. The opinions expressed within this communication are not necessarily those expressed by Reed Exhibitions. Visit our website at http://www.reedexpo.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:203011 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
