Re: Taille du swap

[Olivier Abad <oabad@noos.fr>]

On Mon, Mar 05, 2001 at 09:13:24AM +0100, Patrice KARATCHENTZEFF wrote:
> ext.green.mei@sncf.fr wrote:
> > 
> > Personnellement, j'ai un swap de 512Mo (2x256Mo - noyau 2.4)
> > J'ai fais ca à cause d'un post recent dans la ML disant que
> > pour le 2.4 le 2xRAM était de vigueur. Quand je fais un top
> > je vois bien 512Mo de swap, par contre il est tot le temps
> > vide. Aurais-je donc suivi un mauvais conseil ???
> > 
> 
> oui. Il faut réfléchir avant de faire les choses...

Vu sur kernel-traffic (désolé pour le post en anglais, mais je n'ai pas
le courage de traduire. En résumé, Linus dit que pour le noyau 2.4,
l'équation Swap = 2 x RAM devient vraie) :

http://kt.linuxcare.com/kernel-traffic/kt20010126_104.epl#2

2. Greater 2.4 Swap Requirements
7 Jan - 18 Jan (100 posts) Archive Link: Subtle MM bug

In the course of discussion, it became clear that Linux 2.4.x required
more swap than previous versions. Rik van Riel [*] mentioned, "2.4 keeps
dirty pages in the swap cache, so you will need more swap to run the
same programs..." He asked Linus Torvalds [*], "is this something we
want to keep or should we give the user the option to run in a mode
where swap space is freed when we swap in something non-shared ?" Linus
replied:

  I'd prefer just documenting it and keeping it. I'd hate to have two
  fairly different modes of behaviour. It's always been the suggested
  "twice the amount of RAM", although there's historically been the
  "Linux doesn't really need that much" that we just killed with 2.4.x.

  If you have 512MB of RAM, you can probably afford another 40GB or so
  of harddisk. They are disgustingly cheap these days.

Olivier
-- 
The universe is all a spin-off of the Big Bang.