Fwd: Total vs per-cpu memory

Sorry for the mistake, although otherwise clear from the context: 16GB total is
correct as there are 4GB per cpu.
francesco

--- Francesco Pietra <chiendarret@xxxxxxxxx> wrote:

Date: Thu, 31 Jan 2008 07:39:43 -0800 (PST)
From: Francesco Pietra <chiendarret@xxxxxxxxx>
Subject: Total vs per-cpu memory
To: debian64 <debian-amd64@xxxxxxxxxxxxxxxx>

This question is related to problems in running a docking computation. With
big
cases, RAM proves insufficient, resulting in immediate "segmentation fault",
so
that "top" cannot inform. Though, from the code it is clear that memory is
insufficient to rotate the object in a non-parallelized part of the program.
Smaller objects do not give problems.

My question is: with Tyan S2895 Thunder K8WE, two dual opterons and 1GB RAM
per
cpu (amd64 etch), are the 16GB available to the single cpu involved in the
computation, or are 4GB available?

Memory was set with shmmax:

kernel.shmmax = 16000000000
kernel.shmall = 16000000000

sysctl -p

Thanks
francesco pietra




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