Hi Patrick, Thank you for your response. I read that the default was 1024K and that there are a few approaches that can affect the performance. I read that here http://nfs.sourceforge.net/nfs-howto/ar01s05.html Furthermore I see the following when I use `dd` as suggested on the page when writing a chunks of 16K. The result is: $ time dd if=/dev/zero of=testfile bs=16k count=16384 16384+0 records in 16384+0 records out 268435456 bytes (268 MB) copied, 7.4459 s, 36.1 MB/s real 0m7.447s user 0m0.001s sys 0m0.195s The following secction on the page suggests to increase memory limits 5.7. Memory Limits on the Input Queue .... .... # echo 262144 > /proc/sys/net/core/rmem_default # echo 262144 > /proc/sys/net/core/rmem_max .... .... My current settings are: $ cat /proc/sys/net/core/rmem_default 229376 $ cat /proc/sys/net/core/rmem_max 229376 This line here: rw,relatime,vers=3,rsize=8192,wsize=8192,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.0.6.9,mountvers=3,mountport=35079,mountproto=udp,fsc,local_lock=none,addr=10.0.6.9 is handled by autofs which is configured through (FreeIPA). I could increase the wsize and rsize though but not sure what value to define. So for example if I do a `dd` using 8K chunks, the result is: $ time dd if=/dev/zero of=testfile2 bs=8k count=16384 16384+0 records in 16384+0 records out 134217728 bytes (134 MB) copied, 3.0388 s, 44.2 MB/s real 0m3.040s user 0m0.001s sys 0m0.098s And here is the result using 64K chunks: $ time dd if=/dev/zero of=testfile2 bs=64k count=16384 16384+0 records in 16384+0 records out 1073741824 bytes (1.1 GB) copied, 30.8299 s, 34.8 MB/s real 0m30.933s user 0m0.000s sys 0m0.546s On 06/03/2016 04:18 PM, Dave Howorth wrote: > On 2016-06-03 14:49, Patrick J. LoPresti wrote: >>> /Users/users from homeserver.internal.local:/users/users >>> Flags: >>> >> rw,relatime,vers=3,rsize=8192,wsize=8192,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=10.0.6.9,mountvers=3,mountport=35079,mountproto=udp,fsc,local_lock=none,addr=10.0.6.9 >> >> >> How did you wind up with rsize/wsize of 8K? The default on Linux has >> been 1 >> megabyte for a long time. > > Do you have a link for that, please? What is 'a long time'? Does it > apply to all NFS versions and v3 in particular as the OP asked? Is there > a list somewhere of NFS and kernel versions and defaults? > > Cheers, Dave > >> Fix this, and I suspect you will find performance increases dramatically. >> >> - Pat >> -- Valentin Bajrami Kapteyn Astronomical Institute University of Groningen Postbus 800 NL-9700 AV Groningen The Netherlands Phone: +31-(0)50-3634068