lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sun, 5 Feb 2017 11:13:16 +0100 From: Michal Hocko <mhocko@...nel.org> To: Mel Gorman <mgorman@...e.de> Cc: 'Andrew Morton' <akpm@...ux-foundation.org>, Hillf Danton <hillf.zj@...baba-inc.com>, 'Johannes Weiner' <hannes@...xchg.org>, 'Minchan Kim' <minchan.kim@...il.com>, 'Rik van Riel' <riel@...hat.com>, linux-mm@...ck.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH] mm, vmscan: Clear PGDAT_WRITEBACK when zone is balanced On Sun 05-02-17 11:11:13, Michal Hocko wrote: > On Fri 03-02-17 20:32:22, Mel Gorman wrote: > > Hillf Danton pointed out that since commit 1d82de618dd ("mm, vmscan: > > make kswapd reclaim in terms of nodes") that PGDAT_WRITEBACK is no longer > > cleared. It was not noticed as triggering it requires pages under writeback > > to cycle twice through the LRU and before kswapd gets stalled. Historically, > > such issues tended to occur on small machines writing heavily to slow > > storage such as a USB stick. Once kswapd stalls, direct reclaim stalls may > > be higher but due to the fact that memory pressure is requires, it would not > > be very noticable. Michal Hocko suggested removing the flag entirely but > > the conservative fix is to restore the intended PGDAT_WRITEBACK behaviour > > and clear the flag when a suitable zone is balanced. > > > > Signed-off-by: Mel Gorman <mgorman@...e.de> > > I agree this is a more conservative approach but I think removing > PGDAT_WRITEBACK should simplify things a bit. > > Acked-by: Michal Hocko <mhocko@...e.com> Ohh, an please add Fixes: 1d82de618ddd ("mm, vmscan: make kswapd reclaim in terms of nodes") -- Michal Hocko SUSE Labs
Powered by blists - more mailing lists