I would alos suggest leaving an equal amount (or thereabouts) of RAM to the OS for native allocation. I found - after months of fighting, that assigning too much to the JVM heap can also have detrimental effects.
Another thing to look at is to drop the native stack size allocated to threads - the default on Windows is 1024k as far as my research found - thus within the 2GB allocation of memory to a single process that would limit the number of threads that can be spawned within that space. This is set with the -Xssxxxk setting - I have set mine to -Xss128k - which 'theoretically' would allow 8 times (a VERY rough estimate) the number of threads within the allocated heap. One other setting that I found useful was the perm gen space allocation - for classloading etc. The default I believe is 64MB, however, if you have a large number of webappclassloaders within your Tomcat space - pushing this up would be useful - especially if you trigger redeploys etc. This can be set with the -XX:MaxPermSize=xxm setting - the value of which should be determined based on total OS RAM and JVM heap allocations. Anyway, those just some things that I found assisted with my memory issues! Regards, Carl -----Original Message----- From: Caldarale, Charles R [mailto:[EMAIL PROTECTED] Sent: 02 December 2005 23:09 To: Tomcat Users List Subject: RE: memory limit for tomcat? > From: joon yoo [mailto:[EMAIL PROTECTED] > Subject: memory limit for tomcat? > > The server is going to be upgraded to 2GB's of RAM, exactly what is > the limit of the amount of memory that can be allocated to tomcat and > still run stably? The limit is a function of the OS and JVM you're using and anything else running on the box, not Tomcat itself. Windows normally gives each process a 2 GB virtual space to play in, and then scatters various dlls through it to guarantee not having contiguous space. Without going to great pains, the largest heap you can use on a Windows server is around 1.3 - 1.5 GB. If you set the -Xmx value to something that large, watch your paging rate carefully to make sure you don't start thrashing. - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers. --------------------------------------------------------------------- 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]
