Re: [squid-users] mlockall or plock: Any advantage?

You should simply avoid creating a situation where Squid might be
swapped out.

In other words, Squid getting swapped out is very bad...but part of the
reason it is so bad is that if there is that much memory pressure on
your system disk I/O will suffer, crippling Squids performance.
Actually having the Squid process go into swap memory is even worse--but
it's just a symptom of other problems (too big a Squid process for the
amount of memory you have--shrink your Squid or grow your memory).

So it is not /just/ the fact of Squid being swapped out that is so bad
for performance though it certainly does get ugly if any swapping occurs
of the Squid process--but /something/ will have to go into swap if you
have that much memory usage pressure on the system, and so performance
will suffer generally, regardless of what it is.

That said, it probably wouldn't hurt--but please don't consider it a
solution to an existing problem.

Just my .02.

Jim Richey wrote:

> Is their any advantage to using mlockall (Linux) or plock (bsd?) to
> prevent squid, or parts of it, from being swapped out?

-- 
Joe Cooper <joe@swelltech.com>
http://www.swelltech.com
Web Caching Appliances and Support