[Beowulf] NFS Performance using SLES 10

[Alan Louis Scheinine]

Tim Moore wrote:
>  When I observed 
> the IO status, I saw that I could probably write the file by hand faster 
> than the 2nd node was writing the files to the server.  I would have to 
> check but I think the mobo has integrated broadcom ethernet.  I have 
> tried the usual tweaks with respect to rsize and wsize and performance 
> seemed to worsen if it changed at all.

What values of rsize and wsize?  My experience is with UDP whereas you use TCP,
but in any case, my experience is the following, for autofs
  rsize=4096,wsize=4096
works well and larger values cause too much overhead with fragmented packets.
Also, in my experience the fragmented packet problem only occured for large
files.  For a continuous tranfer, the I/O is fast for the first few seconds
then the traffic-jam.
best regards,
Alan
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