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: Tue, 21 May 2019 08:34:21 +0200 From: Michal Hocko <mhocko@...nel.org> To: Matthew Wilcox <willy@...radead.org> Cc: Minchan Kim <minchan@...nel.org>, Andrew Morton <akpm@...ux-foundation.org>, LKML <linux-kernel@...r.kernel.org>, linux-mm <linux-mm@...ck.org>, Johannes Weiner <hannes@...xchg.org>, Tim Murray <timmurray@...gle.com>, Joel Fernandes <joel@...lfernandes.org>, Suren Baghdasaryan <surenb@...gle.com>, Daniel Colascione <dancol@...gle.com>, Shakeel Butt <shakeelb@...gle.com>, Sonny Rao <sonnyrao@...gle.com>, Brian Geffon <bgeffon@...gle.com>, linux-api@...r.kernel.org Subject: Re: [RFC 0/7] introduce memory hinting API for external process [linux-api] On Mon 20-05-19 18:44:52, Matthew Wilcox wrote: > On Mon, May 20, 2019 at 12:52:47PM +0900, Minchan Kim wrote: > > IMHO we should spell it out that this patchset complements MADV_WONTNEED > > and MADV_FREE by adding non-destructive ways to gain some free memory > > space. MADV_COLD is similar to MADV_WONTNEED in a way that it hints the > > kernel that memory region is not currently needed and should be reclaimed > > immediately; MADV_COOL is similar to MADV_FREE in a way that it hints the > > kernel that memory region is not currently needed and should be reclaimed > > when memory pressure rises. > > Do we tear down page tables for these ranges? That seems like a good > way of reclaiming potentially a substantial amount of memory. I do not think we can in general because this is a non-destructive operation. So at least we cannot tear down anonymous ptes (they will turn into swap entries). -- Michal Hocko SUSE Labs
Powered by blists - more mailing lists