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I have a NFS server running Linux and exporting a couple of shares. Both Linux and MacOS clients connect to the server, and while with the Linux clients I get ~ 75MB/s write speed, the MacOS clients only get ~ 25MB/s write speed (same file, same distance from server, same switch, etc ...).

What are possible reasons for this drastic difference in performance? I've already tried to tune the NFS connection on the Mac by editing /etc/nfs.conf

nfs.client.allow_async = 1
nfs.client.nfsiod_thread_max = 128

With these settings I'm at least up from previously 15MB/s to now 25MB/s. However, this is still sooo far away from what I get on the linux boxes.

How should I further debug this? Is there some special way that I should export these shares for macos?

Here's my /etc/auto_master in case you want to see the NFS options that I'm using:

/home   auto_home    -nobrowse,hidefromfinder,resvport,intr,hard,sloppy

EDIT: I know that this must be a NFS issues because I can copy files between the MacOS client and Linux NFS server with scp and there I get ~ 60MB/s.

share|improve this question
Which NFS version do you use? Is there a firewall active on the MAC-side? – Nils Jul 23 '13 at 21:11
no firewall; NFSv3 – memyself Jul 24 '13 at 8:16
Just as a test, try using tcp and running: (this is temporary); sysctl -w "net.inet.tcp.sendspace=4096000"; sysctl -w "net.inet.tcp.recvspace=4096000"; sysctl -w "net.inet.tcp.local_slowstart_flightsize=16"; sysctl -w "net.inet.tcp.delayed_ack=8"; sysctl -w "net.inet.tcp.autorcvbufmax=786432"; sysctl -w "net.inet.tcp.slowlink_wsize=32768" – Aaron Jul 17 '15 at 16:00

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