That statement is only correct if memory footprint is an issue, or if each thread allocates a lot of dynamic memory that isn't shared by other threads. If there isn't much memory required, or if most of the data stored in memory is heavily shared, adding more memory will not increase performance.
Each processor has it's own on-die memory caches, which affect performance more than the amount of RAM all together (especially with good memory locality design). If all threads are trying to access an object that resides in the memory local to processor 1, adding more memory won't change the fact that access to this object from other processors will require non-local memory access through CPU boundaries. Regards, Justin Randall Sent from my BlackBerry device -----Original Message----- From: David Kerber <dcker...@verizon.net> Date: Sun, 24 Apr 2011 08:54:35 To: Tomcat Users List<users@tomcat.apache.org> Reply-To: "Tomcat Users List" <users@tomcat.apache.org> Subject: Re: Tomcat Configuration in Multi Core Systems On 4/24/2011 3:07 AM, sujikin wrote: > Hi, > > Thanks for your replies. I was sure Server B will never will be able to > match Server A even if it had > infinite processors in it ( provided everything remains the same). Just > wanted to confirm. > > @David > Server B has *116* processors only. > Slow because of time taken to handle single request. 32Gb shared among 116 processors isn't very much RAM for each process (that's why I assumed it was 16, not 116). You'll likely get a performance boost if you can give it more RAM. > Regards, > Sujeet > > > > David Kerber wrote: >> On 4/23/2011 2:31 PM, Sujeet Singh wrote: >>> Hi, >>> >>> I have two servers which has below configuration, >>> >>> Server A has 32 GB RAM, 4 processors each of 2.8 GHz >>> >>> Server B has 32 GB RAM, 116 processors each of 1.6 GHz. >>> >>> Both servers has tomcat installed having same configuration. >>> >>> Tomcat of server B is at least half as slow as Server A. >>> >>> My question is...just by increasing the worker thread count, the >>> performance >>> of >>> Server B can be increased or we need to do something else also? >>> >>> Tomcat version is 5.5 and Java version is 5. OS used is Solaris 10 SPARC. >>> >>> Thanks& Regards, >>> Sujeet >>> >> First, I assume you mean "16" processors in server B, rather than 116. >> >> You need to define "slow": time to process a single request, or # of >> requests it can handle? >> >> Server B's clock speed is about half that of A, so I would expect >> (everything else being equal) that it would run at ~ half the speed of A >> for a single request. However, given that it has 4x as many processors, >> it should be able to handle ~ 4x as many simultaneous requests, but each >> of them will still take about 2x as long as they would on A. >> >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org >> For additional commands, e-mail: users-h...@tomcat.apache.org >> >> >> --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
