Subject: Re: lazy mlock?
To: Wojciech Puchar <firstname.lastname@example.org>
From: Allen Briggs <email@example.com>
Date: 04/18/2002 09:13:14
On Thu, Apr 18, 2002 at 08:59:44AM +0200, Wojciech Puchar wrote:
> ulimit can limit locked memory.
True, but that doesn't help solve the problem. If I'm writing an
application with the approximate size, configurability, and complexity
of ntp, I don't necessarily know which parts of the application
will be in use, how much stack space will be used, etc. If I don't
want the necessary parts to be paged out, but I don't know what my
working set is, I am forced to attempt to mlock() more than I
strictly need because I don't *know* what I necessarily need.
ulimit can limit the amount of locked memory, sure, but that doesn't
help optimize the amount that will be locked--it may simply prevent
the application from running.
I think the lazy mlock() is an excellent way for the kernel and
application to work together in a way that minimizes overall program
(application + kernel) complexity while maximizing efficiency.
This makes sense to me and seems to be a natural extension of a
demand-paged virtual memory system as a whole.
Allen Briggs firstname.lastname@example.org
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