[Gluster-users] Usage Case: just not getting the performance I was hoping for

[Jeff Darcy]

On 03/15/2012 12:09 AM, D. Dante Lorenso wrote:
> After tweaking settings the best we could, we were able to copy files 
> from Mac and Win7 desktops across the network but only able to get 50-60 
> MB/s transfer speeds tops when sending large files (> 2GB) to gluster. 
> When copying a directory of small files, we get <= 1 MB/s performance!
> 
> ...
> 
> When using a single Win2008 server with Raid 10 on 4 drives, shared to 
> the network with built-in CIFS, we get much better (near 2x) performance 
> than this 8-server gluster setup using Samba for smb/cifs and a total of 
> 16 drives.

Please bear in mind that GlusterFS in general is optimized for aggregate
bandwidth, and single-stream bandwidth is often dominated by the *latency* of
the underlying network.  Combine this with the fact that the replication piece
in particular is very latency-sensitive, and a single copy with replication
becomes very much a worst case.  If what you're looking for is bandwidth, I
suggest testing with many I/O streams and ideally many clients.  If you're more
concerned with latency, you should probably measure that at both the network
and storage levels, in addition to using the GlusterFS tools to measure at that
level.  That should give you some ideas about where you can drive out latency
and improve performance for those use cases.