Messages in this thread |  | | Date | Mon, 24 Sep 2001 19:39:38 -0300 (BRT) | From | Marcelo Tosatti <> | Subject | Re: 2.4.10 VM: what avoids from having lots of unwriteable inactive pages |
| |
On Mon, 24 Sep 2001, Linus Torvalds wrote:
> > On Mon, 24 Sep 2001, Marcelo Tosatti wrote: > > > > What avoids us from having a lot of unfreeable (eg mapped by ptes) pages > > on the inactive list ? > > Nothing. > > If we can't shrink them, we'll fall out and do vmscanning. > > Which is exactly what we want to do - it automatically acts as a "uhhuh, > we've got to do something now" thing.
Think about a case where the inactive list if _full_ of mapped pages. (which can easily happen, because one fault (do_swap_page) will _not_ move the page to the active list directly --- it has to be accessed (Referenced bit) twice (mark_page_accessed)).
We _think_ we don't have a shortage, so we won't call refill_inactive().
We keep calling swap_out(), which will not deactivate pages which _can_ be written out, until we deactivate the pte's from the pages which are on the inactive list.
Nothing prevents that, right ?
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |