cvs pserver performance

[Russ Tremain]

Hi -

I've reviewed much of the discussion on this list on
CVS server performance, in hopes of finding something related
to the problems we are experiencing our CVS server.  So far, I
haven't found anything similar to what we are experiencing.
Apologies if this is a re-hash.

We are running cvs 1.10.8 as a pserver on a rather beefy
solaris system.  Our repository is fairly large and contains
about 45,000 files.  This machine is idle most of the time,
and its only job is to run the CVS server.

Performance is adequate when one client does a full CVS update.
This update takes 15-20 minutes.

When a second client updates, both updates slow substantially,
taking about 35-40 minutes.

When three clients are updating simultaneously, the update
time starts to climb to about 1.5 hours per client.

Surprisingly, the packet traffic goes *down* as more clients
attach.

When a truss a client that is particularly slow, I find
that it is loosing, (and therefore requesting a retransmit of,)
about every third packet.

When I snoop on the ethernet interface, I find that all clients
are sending to the server port 2401.

I was surprised by this, since most servers only listen on
a well-known socket for connections, negotiate a private socket
to handle a particular client, and then use this new socket for
further communications.

My understanding is that if a bunch of processes are reading
the same socket, then the packet is consumed by the first
reader.

Therefore, the retransmits would make sense as a source of the
poor performance we are experiencing when we have multiple
updates running.

Tell me it isn't true...

If it is true, then is there an easy work-around?  I would like to
retain the pserver strategy...but I suppose we could revert to NFS
for subsets of clients.

Thanks for any help or suggestions...

Regards,
-Russ

Russ Tremain
address@hidden

Senior Architect, Infrastructure Engineering
Forte Tools Division
Sun Microsystems, Inc.