> I've heard that too, but it doesn't seem to make much sense
> to me. If
> you get to the point where your machine is _needing_ 2GB of swap then
> something has gone horribly wrong (or you just need more RAM in the
> machine) and it will just crawl until the kernel kills off whatever
> process causes the swap space to be exceeded. Seems to me that you
> should only have that much swap if you can't afford more RAM
> or you've
> tapped out your machine's capacity, and your application needs that
> much memory.
I've heard the same, the reason behind it was that there needs to be
one-to-one copy of the memory to be able to swap out everything and to
have a gain in the total "memory", you'd need twice as much swap as
memory to have a doubling of your memory.
But afaik this behaviour has been adjusted since the 2.4.5 kernel and
isn't a real issue anymore.
Please keep in mind that I'm no expert at all on linux, so if you want
to be sure, you'd better mail to the kernel-mailinglist orso :)
Anyway, I manage a few machines with 1GB++ memory and none of them has
more than 1G of swap and none of them uses that swap for more than a few
MB unless something was terribly wrong, so the actual 'risk' probably
doesn't have a high chance to occur.
In response to
pgsql-performance by date
|Next:||From: Bruno BAGUETTE||Date: 2003-06-28 09:17:42|
|Subject: RE : Large querie with several EXISTS which will be often runned|
|Previous:||From: scott.marlowe||Date: 2003-06-27 20:51:25|
|Subject: Re: Memory question|