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[PATCH 0/2] x86: fix memory leaks when doing CPU hotplug

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From: Andreas Herrmann
Subject: [PATCH 0/2] x86: fix memory leaks when doing CPU hotplug
Date: Wednesday, August 6, 2008 - 1:24 am

Following patches fix two memory leaks with CPU hotplug.
Some per CPU data is allocated each time a CPU is set online.
But this space is never freed.

Usually this memory leak is not a big deal (for normal CPU hotplug usage).
But during stress tests with lots of CPU offline/online cycles this
really matters.

The entire leak is 40K (10 pages) for each offline/online cycle per
CPU.  I've verified both fixes performing more than 90000 CPU
offline/online cycles.

This is not a regression but I think it's still 2.6.27 material.
Please apply.


Regards,

Andreas


BTW, there is still a leak of about 600 bytes per offline/online cycle
per CPU -- according to slabinfo this might be sysfs related. The most
suspicious entries are:

Name                   Objects Objsize    Space Slabs/Part/Cpu  O/S O %Fr %Ef Flg
sysfs_dir_cache         266085      80    41.9M      10235/4/0   26 0   0  50 PZFU
kmalloc-8               130870       8    10.5M       2568/5/0   51 0   0   9 PZFU


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Messages in current thread:
[PATCH 0/2] x86: fix memory leaks when doing CPU hotplug, Andreas Herrmann, (Wed Aug 6, 1:24 am)
[PATCH 1/2] x86: pda_init(): fix memory leak when using CP ..., Andreas Herrmann, (Wed Aug 6, 1:27 am)
[PATCH 2/2] x86: cpu_init(): fix memory leak when using CP ..., Andreas Herrmann, (Wed Aug 6, 1:29 am)
Re: [PATCH 0/2] x86: fix memory leaks when doing CPU hotplug, Ingo Molnar, (Mon Aug 11, 12:40 pm)
Re: [PATCH 0/2] x86: fix memory leaks when doing CPU hotplug, Andreas Herrmann, (Tue Sep 2, 12:14 am)