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Re: [ccp4bb]: NFS Performance



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Hi Martin,
	What u need to do is to goto /etc/fstab and look for the nfs entries. The 
default is rsize=8192,wsize=8192. U need to increase both numbers by 
multiples of 1024 until the speed improvement is good enough for the 
transfer. U could try doubling both numbers and see what happens. Be sure to 
unmount and remount the filesystem each time (both on the client and, if you 
are zealous, locally on the server as well), which should clear out any 
caches. This only applies if u r using NFSv3 which is the case if u r using 
RHL 7.2

good luck
tommy



> the Linux box requires access to this filesystem. The problem seems to
> occur during read/writes of large binary files, which cause programs to
> slow to a crawl, in some cases increasing the run time by two orders of
> magnitude. I have noticed that the programs processor usage often drops to
> < 1% when this occurs and the machine rapidly runs out of memory (1GB
> real!) If the same process is run on the local (ext3) disc only, or on the
> SGI machines, there are no such problems. Obviously the problem lies with
> the Linux-IRIX disc cross-mounting, but so far I have not been able to see
> where, and the documented NFS options do not seem to help. Has anyone else
> noticed this problem, or suggest any solutions ?
>
> Regards
>
> Martin Singleton
> Cancer Research UK
> Clare Hall Laboratories,
> South Mimms,
> Herts EN6 3LD
> martin.singleton@cancer.org.uk