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Re: Quick question.


From: "Alexei Roudnev" <alex () relcom net>
Date: Wed, 4 Aug 2004 21:54:11 -0700


I am sorry, but I do not  make a theory - I just repors practical results. 2
CPU systems are much more stable than 1 CPU system, in my experience. You
are free to find an explanatiion, if you want -:).




On Wed, 4 Aug 2004, Paul G wrote:

the second cpu buys you time - it is unlikely you're going to be
able to react in time on a busy single cpu box with a runaway
process (it launches into a death sprial almost immediately), but
you would usually have 10-15 mins on a dual cpu box at a minimum or
maybe infinity if you enforce cpu affinity for apps that tend to
misbehave.

Why do you have 10-15 mins? If the application is multi-threaded and
has a reasonable workload, there are plenty of types of bugs that
will result in one spinning thread after the other, you need far
more than just 2 CPUs! Or maybe your application vendor has "at least
10minutes between hitting bugs!" on it's feature list? ;)

Really, what you to need do is (in the face of such buggy apps) is to
set per-task CPU time resource limits appropriate to how much
cpu-time a task needs and how much you can afford - be it a 1, 2 or n
CPU system.

paul

regards,
-- 
Paul Jakma paul () clubi ie paul () jakma org Key ID: 64A2FF6A
Fortune:
I came to MIT to get an education for myself and a diploma for my mother.


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