[Gluster-users] GlusterFS performance

[Joe Landman]

On 09/26/2012 05:28 PM, John Mark Walker wrote:
>
>
> On Wed, Sep 26, 2012 at 2:23 PM, Berend de Boer <berend at pobox.com
> <mailto:berend at pobox.com>> wrote:
>
>      >>>>> "John" == John Mark Walker <johnmark at johnmark.org
>     <mailto:johnmark at johnmark.org>> writes:
>
>          John> This is different from any other benchmark I've seen. I
>          John> haven't seen that much of a disparity before.
>
>     What benchmarks? Steve's experience is very similar to what everyone
>     sees when trying out gluster.
>
>
> Have you seen write:read ratios > 5:1? I certainly haven't. I have seen
> discrepancies, sure, but not by that much.

I've seen stuff like this.  Looks like a caching issue (gluster client) 
among other things.

Read performance with the gluster client isn't that good, write 
performance (effectively write caching at the brick layer) is pretty good.

I know its a generalization, but this is basically what we see.  In the 
best case scenario, we can tune it pretty hard to get within 50% of 
native speed.  But it takes lots of work to get it to that point, as 
well as an application which streams large IO.  Small IO is a (still) 
bad on the system IMO.

I've not explored the 3.3.x caching behavior (largely turned it off in 
3.2.x and previous due to bugs which impacted behavior).




-- 
Joseph Landman, Ph.D
Founder and CEO
Scalable Informatics Inc.
email: landman at scalableinformatics.com
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