heavy volume ftp problem

[Aaron Solochek <aarons@andrew.cmu.edu>]

I have a sparc 5 running potato, and proftpd.  It have a 170Mhz
processor, and 128mb of ram.  The issue is that under heavy ftp loads,
for instance transferring 1.3gb at around 600k/sec caused this, the
system develops defunt processes.  These processes are usually sshd,
imapd, and other network related processes, but also sometimes
bash(although that is probably related to the dead ssh connections).  Is
this a hardware problem or software?  Could a bad nic cause this?

-Aaron Solochek
 leko@cmu.edu