bad NFS/UDP performance

[Robert Watson]

On Sat, 4 Oct 2008, Danny Braniss wrote:

> at the moment, the best I can do is run it on a different hardware that has 
> if_em, the results are in
> 	ftp://ftp.cs.huji.ac.il/users/danny/lock.prof/7.1-1000.em the 
> benchmark ran better with the Intel NIC, averaged UDP 54MB/s, TCP 53MB/s (I 
> get the same numbers with an older kernel).

Dear Danny:

Unfortunately, I was left slightly unclear on the comparison you are making 
above.  Could you confirm whether or not, with if_em, you see a performance 
regression using UDP NFS between 7.0-RELEASE and the most recent 7.1-STABLE, 
and if you do, whether or not the RLOCK->WLOCK change has any effect on 
performance?  It would be nice to know on the same hardware but at least with 
different hardware we get a sense of whether or not this might affect other 
systems or whether it's limited to a narrower set of configurations.

Thanks,

Robert N M Watson
Computer Laboratory
University of Cambridge