[PVFS-users] Poor performance

[Jeffrey B. Layton]

Nathan Poznick wrote:

>Thus spake Jon Combe:
>  
>
>>I've tried the count again this morning (when it would presumably have
>>expired from the cache). It still runs in 4 seconds.
>>    
>>
>
>Only time does not expire things from the cache, only dirtying of the
>pages by modification or being pushed out by other cached pages.
>Running in 4 seconds would equate to 369.4066 megabytes per second,
>which is clearly running from memory.
>  
>
   Nathan is correct. 4 seconds is not realistic for
disk access times on a remote system. What are the
NFS export options on the server? What are the
mount options on the client?
   I would recommend going to the NFS website
(nfs.sourceforge.net) and reading some of the
documentation there (in particular look at the
sync option). You can also get on the NFS mailing
list and ask questions there (although please read
the documentation first).
   Then you can twiddle the NFS export and client
mount options to get a better comparison to PVFS.

Jeff