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mickey
December 11th, 2009, 07:32
Now that all machines in my network are upgraded from 7.2 to 8.0-RELEASE-p1, I am noticing a significant NFS performance decrease on my notebook.

The notebook is connected via wireless LAN, the NFS server is on a wired subnet, so both machines are on different physical network segments. I have been using NFSv3 with TCP mounts quite some time with 7.2 without seeing any unusual problems.

Now with 8.0 on client/server, directory listings seem to take unusually long. For example ls -al /usr/ports/sysutils on an NFS mounted /usr/ports takes 1:49.60.

I have tried various mount options, including rsize=1024, but have not had any luck so far. The firewall on the router does not show any dropped packets either. Using the same NFS mount on a machine connected to the wired network performs normal.

Any suggestions are highly appreciated.
DutchDaemon
December 11th, 2009, 07:37
Does an 'ls' or an 'ls -aln' go faster? If so, maybe user/group mapping are problematic.
mickey
December 11th, 2009, 08:59
Does an 'ls' or an 'ls -aln' go faster? If so, maybe user/group mapping are problematic.


# time ls /usr/ports/sysutils
0.135u 0.031s 0:00.29 55.1% 31+1058k 0+0io 0pf+0w

# time ls -aln /usr/ports/sysutils
0.182u 0.336s 1:08.88 0.7% 33+1155k 0+0io 0pf+0w

That's quite a big difference. How comes? And why hasn't this been a problem with 7.2?

For comparison, the same taken on a machine connected to the wired ethernet:

# time ls /mnt/sysutils
0.073u 0.026s 0:00.57 15.7% 40+1321k 0+0io 0pf+0w

# time ls -aln /mnt/sysutils
0.056u 0.106s 0:01.99 7.5% 41+1456k 0+0io 0pf+0w


I could verify, that another notebook connected via the same wireless lan does show the same symptoms.
mickey
December 12th, 2009, 06:32
Some further investigation into this issue has revealed, that disabling the use of fast frames on the wireless network keeps the NFS problem from occurring.

I am still at a loss though to understand fully, why this problem arises with fast frames enabled in the first place, and whether there is a solution to get both working together, which would be desirable.