[Gluster-users] GlusterFS throughput inconsistent

[Ben Turner]

----- Original Message -----
> From: "Deepak Naidu" <dnaidu at nvidia.com>
> To: gluster-users at gluster.org
> Sent: Wednesday, February 22, 2017 3:36:22 PM
> Subject: [Gluster-users] GlusterFS throughput inconsistent
> 
> 
> 
> Hello,
> 
> 
> 
> I have GlusterFS 3.8.8. I am using IB RDMA. I have noticed during Write or
> Read the throughput doesn’t seem consistent for same workload(fio command).
> Sometimes I get higher throughput sometimes it quickly goes into half, then
> stays there.

This is strange, if it were me I would try to create a TCP volume transport instead of RDMA and see if you can reproduce there.

> 
> 
> 
> I cannot predict a consistent behavior every time when I run the same
> workload. The time to complete varies. Is there any log file or something I
> can look into, to understand this behavior. I am single client(fuse) running
> 32 thread, 1mb block size, creating 200GB or reading 200GB files randomly
> with directIO.

To see upto +-5-10% variance between runs is normal(closer to 5%, 10 is a little high).  I haven't seen a 50% like you mentioned above, like I said I wonder if this is reproducible on a TCP transport volume?  Can you provide some FIO output from a few runs for us to have a look at?

-b


> 
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> 
> Deepak
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