some simple nfs-benchmarks on 5.4 RC2

[Eric Anderson]

Claus Guttesen wrote:
>>What does gstat look like on the server when you are doing this?
>>Also - does a dd locally on the server give the same results?  You should get
>>about double that I would estimate locally direct to disk.  What about a dd over
>>NFS?
> 
> 
> dd-command:
> 
> dd if=/dev/zero of=/nfssrv/dd.tst bs=1024 count=1048576
> 
> on client:
> 1073741824 bytes transferred in 24.787112 secs (43318553 bytes/sec)
> gstat showed approx. 30.000-52.000 KB/s.
> 
> on nfs-server:
> 1073741824 bytes transferred in 23.368815 secs (45947637 bytes/sec)
> gstat showed approx. 45.000-46.000 KB/s.
> 
> The funny thing is that the outputrate fluxuates more dd'ing from the
> client (remote) and is more consistent dd'ing on the server (locally).
> 
> 
>>What is the server spending its time doing? (top?)
> 
> 
> nfsd.
> 
> 
>>If you are looking for the best performance, you might try a RAID 0+1 (or 10
>>possibly) instead of RAID 5.
> 
> 
> I chosed raid 5 to maximize space.


What state is nfsd in?  Can you send the output of this:

ps -auxw|grep nfsd

while the server is slammed?

I think you are disk bound..  You should not be disk bound at this point with a 
good RAID controller..


Eric






-- 
------------------------------------------------------------------------
Eric Anderson        Sr. Systems Administrator        Centaur Technology
A lost ounce of gold may be found, a lost moment of time never.
------------------------------------------------------------------------