Load problem with ims 5.2

Hello,

We're running IMS 5.2 (I know it's old!) on Solaris 8 and suddenly 
seeing some major load issues. It's one of two mailstores running on a 
Sunfire 280R with 6GB. We've been on this hardware for a couple of years 
and never noticed any problems until a couple of weeks ago.

Suddenly on this one machine we see very high loads (up to 700). imapd 
processes are always consuming most of the CPU in top, and the activity 
is pretty evenly divided between user and kernel (ie. no or minimal 
iowait). Here's a top snapshot - load is low right now but it shows 
imapd chewing up all the cpu. At this time we had only 700 imap connections.



last pid:  9266;  load averages: 26.25, 26.14, 
44.50                                                              21:29:56
86 processes:  78 sleeping, 6 running, 2 on cpu
CPU states:  0.0% idle, 58.4% user, 41.6% kernel,  0.0% iowait,  0.0% swap
Memory: 6144M real, 596M swap in use, 4513M swap free

 PID USERNAME THR PRI NICE  SIZE   RES STATE   TIME    CPU COMMAND
8248 mailsrv   33  53   -2  175M   43M run     3:06 51.89% imapd
8219 mailsrv   16  50   -2  184M   41M run     3:37 12.44% imapd
8231 mailsrv   28  50   -2  178M   42M run     3:58  8.79% imapd
8300 mailsrv   23  58    0   28M   21M run     0:42  3.59% tcp_smtp_server
8230 mailsrv   30  59   -2  232M   41M sleep   3:50  2.84% imapd
23887 root      11  58    0  142M  141M sleep 105:58  0.97% bpbkar
8269 mailsrv   10  50   -2  181M   54M run     0:12  0.86% mshttpd
8272 mailsrv   13  59   -2  218M   61M sleep   0:23  0.59% mshttpd

As this came on so suddenly without any configuration changes or major 
addition of users, I was wondering if we have some corrupt database / 
index somewhere, but I really have no idea where to look. Any 
suggestions would greatly appreciated.

Thanks,

Rich