Gigabit performance issues and NFS

Doug Farley d.l.farley at
Thu May 29 09:35:54 EDT 2003

Fellow Wulfers,

I know this isnt 100% wulf related, although it is part of my wulfs setup, 
but this is the best forum where everyone has alot of good experience.

Well Heres the deal, I have a nice 2TB Linux file server with an Intel 
e1000 based nic in it.  And I have an SGI O3 (master node) that is dumping 
to it with a tigon series gigabit card.  I've tuned both, and my ttcp and 
netpipe performance average ~ 80-95MB/s which is more than reasonable for 
me.  Both the fibre channel on my SGI and the raid (3ware) on my Linux box 
can write at 40MB/s sustained, read is a little faster for both maybe ~ 
50MB/s sustained.  I can get ftp/http transfers between the two to go at 
39-40MB/s, which again i'm reasonably happy with.  BUT, the part that is 
killing me is nfs and scp.  Both crawl in at around 8-11MB/s with no other 
devices on the network.  Any exports from the SGI i've exported with the 
32bitclients flag, and i've pumped my r&wsize windows up to 32K, and forced 
nfs v3 on both Linux and Irix.  After spending a week scouring the web I've 
found nothing that has worked, and SGI support thinks its a Linux nfs 
problem, which could be, but i'd like to get the opinion of this crowd in 
hopes of some light!


Doug Farley

Doug Farley

Data Analysis and Imaging Branch
Systems Engineering Competency
NASA Langley Research Center

< Phone +1 757 864-8141 >

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