Re: 2.4.10 VM, active cache pages, and OOM

[Linus Torvalds]

On Sat, 29 Sep 2001, Rik van Riel wrote:
> On Sat, 29 Sep 2001, Linus Torvalds wrote:
>
> > (which basically says: we only mark the page accessed if we read the
> > _beginning_ of the page, or if we just did a seek to it)
>
> That should work for linear IO, but I fear what influence
> such a thing would have on eg. database indexes ;)

Well, for things that seek, the behaviour will be the same as it was
before: it will always mark the page accessed, because "file->f_reada"
will always be zero for the first read after a lseek.

That's why we have the "or if we just did a seek to it". You cannot _just_
test for "did we read the beginning of a page", because that fails for
seekers, whether database or otherwise.

		Linus