[Gluster-users] gluster local vs local = gluster x4 slower

Bryan Whitehead driver at megahappy.net
Wed Mar 24 21:23:54 UTC 2010


I'd like to see results with this:

time ( tar xzf /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz && sync )

I've found local filesystems seem to use cache very heavily. The
untarred file could mostly be sitting in ram with local fs vs going
though fuse (which might do many more sync'ed flushes to disk?).

On Wed, Mar 24, 2010 at 2:25 AM, Jeremy Enos <jenos at ncsa.uiuc.edu> wrote:
> I also neglected to mention that the underlying filesystem is ext3.
>
> On 3/24/2010 3:44 AM, Jeremy Enos wrote:
>>
>> I haven't tried all performance options disabled yet- I can try that
>> tomorrow when the resource frees up.  I was actually asking first before
>> blindly trying different configuration matrices in case there's a clear
>> direction I should take with it.  I'll let you know.
>>
>>    Jeremy
>>
>> On 3/24/2010 2:54 AM, Stephan von Krawczynski wrote:
>>>
>>> Hi Jeremy,
>>>
>>> have you tried to reproduce with all performance options disabled? They
>>> are
>>> possibly no good idea on a local system.
>>> What local fs do you use?
>>>
>>>
>>> --
>>> Regards,
>>> Stephan
>>>
>>>
>>> On Tue, 23 Mar 2010 19:11:28 -0500
>>> Jeremy Enos<jenos at ncsa.uiuc.edu>  wrote:
>>>
>>>> Stephan is correct- I primarily did this test to show a demonstrable
>>>> overhead example that I'm trying to eliminate.  It's pronounced enough
>>>> that it can be seen on a single disk / single node configuration, which
>>>> is good in a way (so anyone can easily repro).
>>>>
>>>> My distributed/clustered solution would be ideal if it were fast enough
>>>> for small block i/o as well as large block- I was hoping that single
>>>> node systems would achieve that, hence the single node test.  Because
>>>> the single node test performed poorly, I eventually reduced down to
>>>> single disk to see if it could still be seen, and it clearly can be.
>>>> Perhaps it's something in my configuration?  I've pasted my config files
>>>> below.
>>>> thx-
>>>>
>>>>      Jeremy
>>>>
>>>> ######################glusterfsd.vol######################
>>>> volume posix
>>>>    type storage/posix
>>>>    option directory /export
>>>> end-volume
>>>>
>>>> volume locks
>>>>    type features/locks
>>>>    subvolumes posix
>>>> end-volume
>>>>
>>>> volume disk
>>>>    type performance/io-threads
>>>>    option thread-count 4
>>>>    subvolumes locks
>>>> end-volume
>>>>
>>>> volume server-ib
>>>>    type protocol/server
>>>>    option transport-type ib-verbs/server
>>>>    option auth.addr.disk.allow *
>>>>    subvolumes disk
>>>> end-volume
>>>>
>>>> volume server-tcp
>>>>    type protocol/server
>>>>    option transport-type tcp/server
>>>>    option auth.addr.disk.allow *
>>>>    subvolumes disk
>>>> end-volume
>>>>
>>>> ######################ghome.vol######################
>>>>
>>>> #-----------IB remotes------------------
>>>> volume ghome
>>>>    type protocol/client
>>>>    option transport-type ib-verbs/client
>>>> #  option transport-type tcp/client
>>>>    option remote-host acfs
>>>>    option remote-subvolume raid
>>>> end-volume
>>>>
>>>> #------------Performance Options-------------------
>>>>
>>>> volume readahead
>>>>    type performance/read-ahead
>>>>    option page-count 4           # 2 is default option
>>>>    option force-atime-update off # default is off
>>>>    subvolumes ghome
>>>> end-volume
>>>>
>>>> volume writebehind
>>>>    type performance/write-behind
>>>>    option cache-size 1MB
>>>>    subvolumes readahead
>>>> end-volume
>>>>
>>>> volume cache
>>>>    type performance/io-cache
>>>>    option cache-size 1GB
>>>>    subvolumes writebehind
>>>> end-volume
>>>>
>>>> ######################END######################
>>>>
>>>>
>>>>
>>>> On 3/23/2010 6:02 AM, Stephan von Krawczynski wrote:
>>>>>
>>>>> On Tue, 23 Mar 2010 02:59:35 -0600 (CST)
>>>>> "Tejas N. Bhise"<tejas at gluster.com>   wrote:
>>>>>
>>>>>
>>>>>> Out of curiosity, if you want to do stuff only on one machine,
>>>>>> why do you want to use a distributed, multi node, clustered,
>>>>>> file system ?
>>>>>>
>>>>> Because what he does is a very good way to show the overhead produced
>>>>> only by
>>>>> glusterfs and nothing else (i.e. no network involved).
>>>>> A pretty relevant test scenario I would say.
>>>>>
>>>>> --
>>>>> Regards,
>>>>> Stephan
>>>>>
>>>>>
>>>>>
>>>>>> Am I missing something here ?
>>>>>>
>>>>>> Regards,
>>>>>> Tejas.
>>>>>>
>>>>>> ----- Original Message -----
>>>>>> From: "Jeremy Enos"<jenos at ncsa.uiuc.edu>
>>>>>> To: gluster-users at gluster.org
>>>>>> Sent: Tuesday, March 23, 2010 2:07:06 PM GMT +05:30 Chennai, Kolkata,
>>>>>> Mumbai, New Delhi
>>>>>> Subject: [Gluster-users] gluster local vs local = gluster x4 slower
>>>>>>
>>>>>> This test is pretty easy to replicate anywhere- only takes 1 disk, one
>>>>>> machine, one tarball.  Untarring to local disk directly vs thru
>>>>>> gluster
>>>>>> is about 4.5x faster.  At first I thought this may be due to a slow
>>>>>> host
>>>>>> (Opteron 2.4ghz).  But it's not- same configuration, on a much faster
>>>>>> machine (dual 3.33ghz Xeon) yields the performance below.
>>>>>>
>>>>>> ####THIS TEST WAS TO A LOCAL DISK THRU GLUSTER####
>>>>>> [root at ac33 jenos]# time tar xzf
>>>>>> /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz
>>>>>>
>>>>>> real    0m41.290s
>>>>>> user    0m14.246s
>>>>>> sys     0m2.957s
>>>>>>
>>>>>> ####THIS TEST WAS TO A LOCAL DISK (BYPASS GLUSTER)####
>>>>>> [root at ac33 jenos]# cd /export/jenos/
>>>>>> [root at ac33 jenos]# time tar xzf
>>>>>> /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz
>>>>>>
>>>>>> real    0m8.983s
>>>>>> user    0m6.857s
>>>>>> sys     0m1.844s
>>>>>>
>>>>>> ####THESE ARE TEST FILE DETAILS####
>>>>>> [root at ac33 jenos]# tar tzvf
>>>>>> /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz  |wc -l
>>>>>> 109
>>>>>> [root at ac33 jenos]# ls -l
>>>>>> /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz
>>>>>> -rw-r--r-- 1 jenos ac 804385203 2010-02-07 06:32
>>>>>> /scratch/jenos/intel/l_cproc_p_11.1.064_intel64.tgz
>>>>>> [root at ac33 jenos]#
>>>>>>
>>>>>> These are the relevant performance options I'm using in my .vol file:
>>>>>>
>>>>>> #------------Performance Options-------------------
>>>>>>
>>>>>> volume readahead
>>>>>>     type performance/read-ahead
>>>>>>     option page-count 4           # 2 is default option
>>>>>>     option force-atime-update off # default is off
>>>>>>     subvolumes ghome
>>>>>> end-volume
>>>>>>
>>>>>> volume writebehind
>>>>>>     type performance/write-behind
>>>>>>     option cache-size 1MB
>>>>>>     subvolumes readahead
>>>>>> end-volume
>>>>>>
>>>>>> volume cache
>>>>>>     type performance/io-cache
>>>>>>     option cache-size 1GB
>>>>>>     subvolumes writebehind
>>>>>> end-volume
>>>>>>
>>>>>> What can I do to improve gluster's performance?
>>>>>>
>>>>>>       Jeremy
>>>>>>
>>>>>> _______________________________________________
>>>>>> Gluster-users mailing list
>>>>>> Gluster-users at gluster.org
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>>>>>> _______________________________________________
>>>>>> Gluster-users mailing list
>>>>>> Gluster-users at gluster.org
>>>>>> http://gluster.org/cgi-bin/mailman/listinfo/gluster-users
>>>>>>
>>>>>>
>>>>>
>>>
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