On the 32 bit system you definitely won't get more the 2G without some kernel hacking and you may well see even less than that.
On the 64 with a 64 bit JVM you should be able to use however much you like obviously leaving some space for the OS to run in. -----Original Message----- From: Leon Rosenberg [mailto:[EMAIL PROTECTED] Sent: 06 October 2005 17:16 To: Tomcat Users List Subject: Re: [OT] How much RAM can java use On 10/6/05, Caldarale, Charles R <[EMAIL PROTECTED]> wrote: > > From: Leon Rosenberg [mailto:[EMAIL PROTECTED] > > Subject: [OT] How much RAM can java use > > > > Does anyone know for sure how much RAM I can use with JAVA 1.4 or 1.5? > > The answer is very platform specific. For example, on a normal 32-bit > Windows system, each process has a maximum of 2 GB to play with, but > some of that is taken up by various .dlls. (And unfortunately, these > are scattered throughout the range, and the Sun JVM insists on having > contiguous space for the heap.) There is a boot option for some > versions of Windows Server that changes the process virtual space to 3 > GB, at the expense of some kernel capacity. > > I've seen 64-bit Sparc systems with Java heaps sized at hundreds of > megabytes... Ok, I'll try to be more specific: Debian 3.1, kernel 2.6.x-smp (32 bit) or Debian 3.1, kernel 2.6.x-smp-emt64 (64 bit) Hardware: AMD Opteron and Xeon64 (both 64 bit) SUN jdk1.5 and/or jdk1.4.2 4 GB total RAM for 32-bit linux, with 3/1 memory partitioning 16GB total RAM for 64-bit linux. thanx leon --------------------------------------------------------------------- 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]
