NFS on 10G interface terribly slow

[Gerrit Kühn]

On Fri, 26 Jun 2015 19:58:42 -0400 (EDT) Rick Macklem
<rmacklem at uoguelph.ca> wrote about Re: NFS on 10G interface terribly slow:


RM> The default (auto tuned) value is reported by "nfsstat -m".
RM> It can be set with a mount option (should be something in "man
RM> mount_nfs"). If you are doing a test with 1 megabyte writes, I'd set
RM> it to at least 1 megabyte. (Basically, writing will be slower for write
RM> (2) syscalls that are larger than wcommitsize. After mav@'s patch, the
RM> difference isn't nearly as noticable. His other commit makes the auto
RM> tuned value more reasonable).
RM> 
RM> If you set it large enough with the "wcommitsize=<N>" mount option, you
RM> don't need the updates stable/10.

Ok, I set it way over 1MB now:

hellpool:/samqfs/K1/Gerrit on /net/hellpool
nfsv3,tcp,resvport,hard,cto,lockd,rdirplus,sec=sys,acdirmin=3,acdirmax=60,acregmin=5,acregmax=60,nametimeo=60,negnametimeo=60,rsize=65536,wsize=65536,readdirsize=8192,readahead=1,wcommitsize=2048576,timeout=120,retrans=2

However, this still gives me the same bad write performance:

root at crest: # dd if=/dev/zero of=/net/hellpool/Z bs=1024k
count=1000 1000+0 records in
1000+0 records out
1048576000 bytes transferred in 22.939049 secs (45711398 bytes/sec)


So I guess I can postpone the update for now, and look for some other
reason for this instead.


cu
  Gerrit