Re: [RFC PATCH 0/5] Fun with the multipathing code

[Trond Myklebust <trondmy@hammerspace.com>]

Hi Olga

On Wed, 2019-01-09 at 14:39 -0500, Olga Kornievskaia wrote:
> Hi Trond,
> 
> Do you have any plans for this patch set?
> 
> I applied the patches on top of 4.20-rc7 kernel I had and tested it
> (linux to linux) with iozone on the hardware (40G link with Mellanox
> CX-5 card).
> 
> Results seem to show read IO improvement from 1.9GB to 3.9GB. Write
> IO
> speed seems to be the same (disk bound I'm guessing). I also tried
> mounting tmpfs. Same thing.
> 
> Seems like a useful feature to include?

Thanks for testing this.

Was this your own port of the original patches, or have you taken my
branch from 
http://git.linux-nfs.org/?p=trondmy/linux-nfs.git;a=shortlog;h=refs/heads/multipath_tcp
?

Either way I appreciate the data point. I haven't seen too many other
reports of performance improvements, and that's the main reason why
this patchset has languished.

3.9GB/s would be about 31Gbps, so that is not quite wire speed, but
certainly a big improvement on 1.9GB/s. I'm a little surprised, tbough,
that the write performance did not improve with the tmpfs. Was all this
using aio+dio on the client?

-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@hammerspace.com