slow file access

[Troy Settle]

All,

I have a 4-STABLE box that's been in service for 5+ years.  Yes, I know 
it's old, but it's been rock-solid, and migration to a new server would 
take days to accomplish, but I fear that's what I'm faced with..

Specs on the server: Dual Xeon 2.8Ghz / 4GB / ~35GB RAID-1 (system) / 
~105GB RAID-5 (mail storage)

For the last week or so, I've been getting spurts of MySQL connection 
failures in my mail logs, but the total number of connections never even 
comes close the max connections allowed for the server.

Occasionally, our website will appear to completely stall for a few 
seconds, and most frustrating of all, when I'm poking around in a shell, 
things will sometimes hang for several seconds while performing certain 
tasks (like cd, ls, tail, etc...).  Even top took like 8 seconds to 
start displaying a process list.  According to raidutil, both raid 
volumes are optimal.  Nothing shows up in syslog.  Here's some info from 
top(1):

last pid:  8799;  load averages:  0.20,  0.43,  0.38  up 35+23:48:22    
14:11:46
263 processes: 2 running, 261 sleeping
Mem: 1027M Active, 2100M Inact, 393M Wired, 178M Cache, 199M Buf, 75M Free
Swap: 4096M Total, 72K Used, 4096M Free

I'm at a loss as to what I should look at next... anyone have any 
suggestions before I commit myself to a VERY long weekend moving 
everything to a new box?

Thanks,

-- 
  Troy Settle
  Pulaski Networks
  866.477.5638