[Gluster-users] tuning gluster performance vs. nfs

[Joe Landman]

On 01/19/2011 04:24 PM, Ryan Williams wrote:
> I have been tweaking and researching for a while now and can't seem to
> get "good" performance out of Gluster.
>
> I'm using Gluster to replace an NFS server (c1.xlarge) that serves
> files to an array of web servers, all in EC2. In my tests Gluster is
> significantly slower than NFS on average. I'm using a distributed
> replicated volume on two (m1.large) bricks:

Hmmm ... we looked through similar concepts (with non-virtualized hosts) 
recently, and found that for large block sequential IO, gluster is 
faster (fewer context switches and less network stack to traverse). 
There was an about 50-60% penalty (basically context switching in the 
fuse layer) associated with the smaller blocks.

To work aruond this, we suggested local caching (if possible) or RAMdisk 
caching.  Use gluster for initial distribution of the files, and then 
copy them to local storage.  Or turn up the client side gluster caching 
so that after initial read, the files come from local cache.



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