Messages in this thread | | | Date | Thu, 23 Mar 2006 19:22:12 +1100 | From | Nick Piggin <> | Subject | Re: [ck] swap prefetching merge plans |
| |
jos poortvliet wrote: > Op donderdag 23 maart 2006 08:04, schreef Con Kolivas: > >>On Thu, 23 Mar 2006 03:53 pm, Andrew Morton wrote: >> >>>A look at the -mm lineup for 2.6.17: >>> >>>mm-implement-swap-prefetching.patch >>>mm-implement-swap-prefetching-fix.patch >>>mm-implement-swap-prefetching-tweaks.patch >>> >>> Still don't have a compelling argument for this, IMO. > > > well, the reason i use it is my computer is much more reactive in the morning. > linux uses to get very slow after a night of not-doing-much except some > 'sleep 5h && blabla' and cron stuff. in the morning it takes a few HOURS to > get up and running smoothly. with swap prefetch, it actually feels faster > compared to a fresh boot. now you can force swap prefetch to start working, i > use it now and then after some heavy taskts which pulled everything to swap. >
I have two issues with this argument (not that I'm trying to say it couldn't make a difference in your case).
Firstly, swap prefetch actually doesn't handle the midnight updatedb pageout problem nicely. It doesn't do any prefetching when the pagecache/vfs cache fills memory (which is what would have to happen for updatedb to push stuff into swap).
Secondly, with or without swap prefetch, I think we can do a better job of handling these use-once patterns to begin with.
-- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com
- 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/
| |