Re: Where did my memory go?
On Sat, 29 Dec 2001, Noah Meyerhans wrote:
> On Sat, Dec 29, 2001 at 01:20:31AM -0500, P Prince wrote:
> >
> > Linux does preemptive swapping. AFAIK, you can't turn it off, and if you
> > could, you probably shouldn't.
> >
> > It will swap out dormant parts of memory, just in case you start up something
> > big, like X, or Netscape, or Emacs. (he he)
> >
> > Under, say, 128MB of RAM, this makes a lot of sense, but when you go to half
> > and gig and beyond, it becomes less useful.
>
> However, under such situations there is no penalty for swapping. The
> swapped pages are cached in RAM. The idea is that the kernel is getting
> a head start just in case it actually *needs* to swap later. If it
> does, all it has to do is re-allocate memory, rather than swap pages out
> to disk and then re-allocate memory. If it had to do that, then a
> situation in which some program suddenly tried to allocate memory would
> cause the system to grind to a halt as pages are swapped out.
>
Noah,
In that case it sounds to me like there is a genuine problem on my
system. Even if the swap is cached in RAM, this doesnt explain the stats
reported by top : the 8M of swap + the total of the RSS column doesnt come
close to the 229M that is reported as being used. Are there any memory
leak issues being reported with the 2.4.16 kernel?
Thanks,
Jor-el
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