Re: Follow-Up on Alexandre's Transparent Huge Pages Testing

[Mark Nelson <mnelson@redhat.com>]

On 09/29/2015 12:59 AM, Dałek, Piotr wrote:
>> -----Original Message-----
>> From: ceph-devel-owner@vger.kernel.org [mailto:ceph-devel-
>> owner@vger.kernel.org] On Behalf Of Mark Nelson
>> Sent: Tuesday, September 29, 2015 1:34 AM
>>
>> Hi Everyone,
>>
>> A while back Alexandre Derumier posted some test results looking at how
>> transparent huge pages can reduce memory usage with jemalloc.  I went
>> back and ran a number of new tests on the community performance cluster
>> to verify his findings and also look at how performance and cpu usage were
>> affected, both during various fio benchmark tests and also during a 4k
>> random write recovery scenario.  I tested tcmalloc 2.4 with 32MB thread
>> cache, 128MB thread cache, and jemalloc 4.0.
>> [..]
>> Here's are the results:
>>
>> https://drive.google.com/file/d/0B2gTBZrkrnpZY3U3TUU3RkJVeVk/view
>
>  From my point of view, this looks excellent. I generally didn't like the idea of moving to Jemalloc because of memory usage increase (which is absurdly high as you can see from the graphs), but with THP disabled things look way better.
> How about trying Jemalloc 4 without THP and with Ceph patched with https://github.com/ceph/ceph/pull/5855? I wonder how much difference it'll give on Incerta.

I actually did try 5855, but there was a nasty monitor memory leak in 
master that prevented the tests from running.  It didn't get fixed until 
early last week and 5855 no longer merges cleanly with latest master.  I 
haven't had time to go back and see what's conflicting, but if you want 
to take a look and update it I would be happy to give it a whirl. :)

Mark

>
>
> With best regards / Pozdrawiam
> Piotr Dałek
>
>
> N�����r��y���b�X��ǧv�^�)޺{.n�+���z�]z���{ay�\x1dʇڙ�,j\a��f���h���z�\x1e�w���\f���j:+v���w�j�m����\a����zZ+�����ݢj"��!tml=
>
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html