On 10/9/05, Dean Michael Berris <[EMAIL PROTECTED]> wrote: > > Unless you're doing a lot of double precision math on your workstation, > you're not going to really need the 64bit processor anyway. Of course, > aside from the fact that in the near future AMD might discontinue the > 32bit processor line, then you have no choice when you upgrade. ;)
On the Xeons with EM64T, performance for our apps (apache httpd/perl/mysql) in general has remained the same, except for those that are memory-bound. On PAE sytems (6GB-8GB), there's a performance penalty we pay, but whereas with 64-bit there aren't any. > Isn't memory management being controlled by the Operating System? Last > time I checked Linux still handles the total amount of memory > addressable by processes running in the system. And the last time I > checked, there was a 4GB limit still on a per-process basis. I dunno > though about 64bit -- but this was true for 32bit. That's right. I forget the nuances, but I think under ia32 it's 4GB virtual address space, the lower 3GB for user-space addresses and the upper 1GB reserved for the kernel addresses. This is true even with PAE. On 64-bit systems, 32-bit processes have a limit of 4GB per process and, theoretically, the total amount of physical memory for 64-bit processes. - gino _________________________________________________ Philippine Linux Users' Group (PLUG) Mailing List [email protected] (#PLUG @ irc.free.net.ph) Read the Guidelines: http://linux.org.ph/lists Searchable Archives: http://archives.free.net.ph
