VegBank

HEre's the email I sent Colby and Bob:

It's been a while since I've paid any attention to the VegBank machine and apparently it has decided it misses me. A user reported a problem with a download, and I saw an error in the log:
DEBUG struts.DownloadAction: executing shell command: /usr/bin/psql -U vegbank -d vegbank -f /usr/local/devtools/jakarta-tomcat/temp/124145486740.tmp --pset null= -n -A -F , -P footer=false
ERROR struts.DownloadAction: IO exception while executing psql
java.io.IOException: java.io.IOException: Cannot allocate memory

So I tried to restart tomcat:
Stopping tomcat: Using CATALINA_BASE: /usr/local/devtools/jakarta-tomcat
Using CATALINA_HOME: /usr/local/devtools/jakarta-tomcat
Using CATALINA_TMPDIR: /usr/local/devtools/jakarta-tomcat/temp
Using JAVA_HOME: /usr/java/1.4
Error occurred during initialization of VM
Could not reserve enough space for object heap

Starting tomcat: Using CATALINA_BASE: /usr/local/devtools/jakarta-tomcat
Using CATALINA_HOME: /usr/local/devtools/jakarta-tomcat
Using CATALINA_TMPDIR: /usr/local/devtools/jakarta-tomcat/temp
Using JAVA_HOME: /usr/java/1.4

I didn't know if this "space" was memory or hard-drive or something else, so I ran df -h:
Filesystem Size Used Avail Use% Mounted on
/dev/sda6 15G 14G 136M 100% /
/dev/sda2 487M 27M 435M 6% /boot
/dev/sda5 29G 21G 7.3G 74% /home
none 1.5G 0 1.5G 0% /dev/shm
/dev/sda3 42G 21G 19G 52% /usr
/dev/sda8 47G 4.8G 40G 11% /var

and I think that the root partition is probably tighter than it should be, but the main dir (/usr and /var) seem ok. I don't really know what's taking up so much space, or what we could do about it, or even if that's really the problem.

top didn't report that anything was gobbling up all the memory.

Anyway, I'm about at the end of my line of things I know how to do without starting to throw restarting commands at everything, so I thought I'd send my query your way to see if you could help guide us in the right direction.