From: Steve Howie (showie@uoguelph.ca)
Date: Thu Jun 05 2003 - 17:55:49 EDT
Howdy,
We have a Sun E450 (Solaris 7) connected to a SunFireV880 (Solaris 8)
over a 100mbps ethernet connection. We are running a large SAS job on
the E450. The dataset used as input to the SAS program is mounted on a
file system residing on an HP XP512 SAN(fibre attached). This works
great. Use this as a performance baseline - elapsed job time for 4 runs
averaged 51 secs.
Now, we unmounted the file system from the E450, remounted it on the
V880, and NFS exported it back to the E450. I won't go into the details
about *why* we are doing this :) Essentially the SAS program is now
reading it's data over an NFS connection.
Naturally, NFS performance was a concern, but I didn't expect it to be
this bad - over 4 runs the elapsed time for the SAS jobs increased to
an average of 4 mins and 10 secs. The job CPU increases a bit too, but
not by nearly a sbig an order of magnitude.
Any ideas how to tweak this to get better performance over the NFS
connection? Using nfsstat -m on the E450 I did notice that Sun uses TCP,
not UDP as their default transport for NFS, so I changed this when
moutning the file system on the E450 to "proto=udp" Basically no
difference in elapsed time.
i.e. mount -F nfs -o proto=udp v880_machine:/users/d/LABOUR /users/d/LABOUR
So.. any ideas? NFS performance patches? other mount options? gigabit
ethernet connection? :)
Thanks in advance,
Steve Howie
-- Academic Services, CCS University of Guelph _______________________________________________ sunmanagers mailing list sunmanagers@sunmanagers.org http://www.sunmanagers.org/mailman/listinfo/sunmanagers
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