From: Michal Hocko <mhocko@kernel.org> To: Andrew Morton <akpm@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de>, Joonsoo Kim <js1304@gmail.com>, Vlastimil Babka <vbabka@suse.cz>, Markus Trippelsdorf <markus@trippelsdorf.de>, <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>, Michal Hocko <mhocko@suse.com> Subject: [PATCH] mm: clarify COMPACTION Kconfig text Date: Tue, 23 Aug 2016 10:09:17 +0200 [thread overview] Message-ID: <1471939757-29789-1-git-send-email-mhocko@kernel.org> (raw) From: Michal Hocko <mhocko@suse.com> The current wording of the COMPACTION Kconfig help text doesn't emphasise that disabling COMPACTION might cripple the page allocator which relies on the compaction quite heavily for high order requests and an unexpected OOM can happen with the lack of compaction. Make sure we are vocal about that. Signed-off-by: Michal Hocko <mhocko@suse.com> --- mm/Kconfig | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/Kconfig b/mm/Kconfig index 78a23c5c302d..0dff2f05b6d1 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -262,7 +262,14 @@ config COMPACTION select MIGRATION depends on MMU help - Allows the compaction of memory for the allocation of huge pages. + Compaction is the only memory management component to form + high order (larger physically contiguous) memory blocks + reliably. Page allocator relies on the compaction heavily and + the lack of the feature can lead to unexpected OOM killer + invocation for high order memory requests. You shouldnm't + disable this option unless there is really a strong reason for + it and then we are really interested to hear about that at + linux-mm@kvack.org. # # support for page migration -- 2.8.1
WARNING: multiple messages have this Message-ID (diff)
From: Michal Hocko <mhocko@kernel.org> To: Andrew Morton <akpm@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de>, Joonsoo Kim <js1304@gmail.com>, Vlastimil Babka <vbabka@suse.cz>, Markus Trippelsdorf <markus@trippelsdorf.de>, linux-mm@kvack.org, LKML <linux-kernel@vger.kernel.org>, Michal Hocko <mhocko@suse.com> Subject: [PATCH] mm: clarify COMPACTION Kconfig text Date: Tue, 23 Aug 2016 10:09:17 +0200 [thread overview] Message-ID: <1471939757-29789-1-git-send-email-mhocko@kernel.org> (raw) From: Michal Hocko <mhocko@suse.com> The current wording of the COMPACTION Kconfig help text doesn't emphasise that disabling COMPACTION might cripple the page allocator which relies on the compaction quite heavily for high order requests and an unexpected OOM can happen with the lack of compaction. Make sure we are vocal about that. Signed-off-by: Michal Hocko <mhocko@suse.com> --- mm/Kconfig | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/Kconfig b/mm/Kconfig index 78a23c5c302d..0dff2f05b6d1 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -262,7 +262,14 @@ config COMPACTION select MIGRATION depends on MMU help - Allows the compaction of memory for the allocation of huge pages. + Compaction is the only memory management component to form + high order (larger physically contiguous) memory blocks + reliably. Page allocator relies on the compaction heavily and + the lack of the feature can lead to unexpected OOM killer + invocation for high order memory requests. You shouldnm't + disable this option unless there is really a strong reason for + it and then we are really interested to hear about that at + linux-mm@kvack.org. # # support for page migration -- 2.8.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next reply other threads:[~2016-08-23 8:09 UTC|newest] Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-08-23 8:09 Michal Hocko [this message] 2016-08-23 8:09 ` [PATCH] mm: clarify COMPACTION Kconfig text Michal Hocko 2016-08-23 8:38 ` Markus Trippelsdorf 2016-08-23 8:38 ` Markus Trippelsdorf 2016-08-23 9:17 ` Michal Hocko 2016-08-23 9:17 ` Michal Hocko 2016-08-25 0:54 ` David Rientjes 2016-08-25 0:54 ` David Rientjes 2016-08-25 6:54 ` Michal Hocko 2016-08-25 6:54 ` Michal Hocko 2016-08-25 22:34 ` David Rientjes 2016-08-25 22:34 ` David Rientjes 2016-08-26 6:44 ` Michal Hocko 2016-08-26 6:44 ` Michal Hocko 2016-08-29 14:10 ` Johannes Weiner 2016-08-29 14:10 ` Johannes Weiner 2016-08-29 14:50 ` Michal Hocko 2016-08-29 14:50 ` Michal Hocko
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1471939757-29789-1-git-send-email-mhocko@kernel.org \ --to=mhocko@kernel.org \ --cc=akpm@linux-foundation.org \ --cc=js1304@gmail.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=markus@trippelsdorf.de \ --cc=mgorman@suse.de \ --cc=mhocko@suse.com \ --cc=vbabka@suse.cz \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.