From: Markus Trippelsdorf <markus@trippelsdorf.de>
To: linux-mm@kvack.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Subject: isolate_freepages_block(): very high intermittent overhead
Date: Mon, 27 Oct 2014 21:40:03 +0100	[thread overview]
Message-ID: <20141027204003.GB348@x4> (raw)
On my v3.18-rc2 kernel isolate_freepages_block() sometimes shows up very
high (>20%) in perf top during the configuration phase of software
builds. It increases build time considerably.
Unfortunately the issue is not 100% reproducible, because it appears
only intermittently. And the symptoms vanish after a few minutes.
I think the "mm, compaction" series from Vlastimil is to blame, but it's
hard to be sure when bisection doesn't work.
-- 
Markus
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next             reply	other threads:[~2014-10-27 20:40 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-27 20:40 Markus Trippelsdorf [this message]
2014-10-27 21:06 ` isolate_freepages_block(): very high intermittent overhead Markus Trippelsdorf
2014-10-27 22:01 ` Vlastimil Babka
2014-10-28  8:59   ` Markus Trippelsdorf
2014-10-29 15:08     ` Vlastimil Babka
2014-11-06 11:42     ` Vlastimil Babka
2014-11-06 11:53       ` Markus Trippelsdorf
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