[Gluster-users] glusterfs performance

[Graeme]

Harald Stürzebecher wrote:
> - telling GlusterFS to always read from local volume:
>
> http://www.gluster.org/docs/index.php/GlusterFS_Translators_v1.3#Automatic_File_Replication_Translator_.28AFR.29
>
> "  # option read-subvolume brick2   # by default reads are scheduled
> from all subvolumes"
>   

Oh yeah, that should make a big difference if I can tell it to just do
reads from the local disks. I was thinking that if it striped reads
across all bricks, then I could potentially get higher read speed by not
limiting it. But since reads aren't striped, then I might as well just
always read locally.

> - making sure it's not your network that kills performance:
> Do you know the maximum throughput of your network connection? Might
> the bottleneck be there? I'd try iperf
> (http://dast.nlanr.net/projects/Iperf/) or something like that and/or
> run some tests with bonnie on a NFS or CIFS share.
>   

I can get 50-80 MB/sec to our local NFS server using iperf, so I think
the gigabit network is performing as expected.

> Do you have a machine with two local disks available? In that case I'd
> try a configuration completely without a physical network, too.
>   

That's a good suggestion, but any machine I've got with multiple disks
already has them in a RAID configuration, so they're not easily
available for this kind of testing.

> - compiling the latest version from source for testing:
> GlusterFS 1.4 is supposed to bring big improvements for small files:
>
> http://www.gluster.org/docs/index.php/GlusterFS_Roadmap#GlusterFS_1.4_-_Small_File_Performance
>   

Yeah. I guess I just didn't think it'd make a big difference since the
bonnie benchmark I've been running uses eight 1GB files, which doesn't
really fall under "small file performance". ;)

Also, we're looking for options to roll out right away, so I pretty much
only want to test the stable release. I understand there's many
improvements in 1.4, but I can't really suggest rolling something out
now based on the development branch. When 1.4 is stable, then that's
what I'll be testing. :)

In any case, I've got some decent ideas for modifying my configuration
and retesting AFR, so that's what I'm going to do. Thanks!

Graeme