samba - Feb 2005 - Slow performance

I noticed that viewing and writing of files from my Windows 2003
server to my Samba Linux server is really slow.  I can see that it's
freezing up for a couple of seconds sometimes.  How do I go about
troubleshooting this problem to figure out where the bottleneck is? 
It just seems so strange because there's not much traffic on the
network and both servers are idle usually (test servers).