[TriLUG] NFS/Netapp Filer with Linux servers

[Jon Carnes]

On Fri, 2004-01-23 at 18:10, Errol Casey wrote:
> I've recently encountered some issues with NFS on linux servers mounting 
> to a Netapp F825 server.
> 
> Linux servers running cgi based shopping cart programs seem to have really 
> slow response. General cgis and web requests are running reasonably well. 
> Only shopping carts seem to be affected by the NFS mounted i/o which seems 
> really werid.
> 
> Monitoring the NFS traffic there is a large amount of getattr, setattr 
> traffic on the Netapp filer.
> 
> I've not been able to find good documentation on what good tuned values 
> are for actimeo are on Linux NFS clients are so the clients are just using
> the defaults that come with the current kernel (2.4.24)
> 
> We have tried udp and tcp (we are using NFS v3).
> 
> Any suggestions? Does anybody have a copy of NFS Illustrated they would be 
> willing to lend, I've tried to find a copy from the library (via 
> inter-library loan but haven't had any luck, don't have the cash handy to 
> go out and by a personal copy).
> 
> Thanks.

You should go directly to the Netapp folks for some advice. I'm sure
they have the specs for tuning the fastest connections to their app.

In general I find that NFS v2 is much faster the v3.  Which means that I
use UDP.  Also I like to boost the packet size and run async (don't wait
for the remote verification):
  rsize=8192,wsize=8192,async

You might be able to optimize your shopping cart app by looking at its
file and disk I/O. A lot of times you can sacrifice some RAM for less
disk I/O.  You might even be able to run a small RAM disk to handle temp
files that are being created now across the NFS link.

HtH - Jon Carnes