[Pvfs2-users] Performance issue using kernel interface

[Sebastian Bauer]

Hi Sam,

Sam Lang wrote:
> Can you walk through your setup and testing environment in a bit more 
> detail?  What kind of performance numbers are you getting from the 
> kernel interface and pvfs2 apps?  Does the performance degrade over time 
> the longer you have the kernel mounted, or does it start off bad?

I installed the pvfs2 server on two servers playing all three roles. 
Furthermore, there are few computers acting as clients only. Using 
pvfs2-cp from a test computer, which is a client only, I get around 
10MB/s which is okay for the 100Mbit ethernet connection. But if I use 
the cp command, I cannot measure anything, it seems to stall (however, 
the destination file grows slowly, but not more than 2kb(!) per second 
on average!

Copying from the pvfs2 to the client-only computer is faster, about 
3MB/s using kernel interface (cp command) whereas the pvfs-cp gives me 
again about 10 MB/s.

It's different when I copy the file from one master to another master.
Concerning the write operation, using the kernel interface, I get around 
9.5MB/s whereas I get 35.71 MB/s using pvfs2-cp (there is a faster 
connection between both master installed)

I've haven't yet done long time tests, but except those 2kb/s everything 
is acceptable in our setting.

Hope this helps. Please tell, if you need anything else to know.

Ciao,
Sebastian