Unable to login during high IO

[TD Clark]

We have a L2000 (hpux 11.0) with 2 cpus and 5.5GB of memory. Most of resources are dedicated to our database - during high i/o users are unable to login. My question is it possible to limit the amount of system I/O to ensure problems like this don't happen? I can provide any kernel information. Thanks!

[harry d brown jr]

This is how you make sure it doesn't happen again:

(1) replace L2000 with RP84XX server - 6 cpus, 12GB of memory, 2X the number of disk IO cards that the L2000 currently has

(2) consider separating your database server from your application server.

(3) move data to high speed SAN using symmetrix, va7400, hitachi, ...

live free or die
harry

[Jeff Schussele]

Hi Todd,

What messages, if any, do the users receive when they can't login?
Do they get a login: prompt?
Do they get a Password: prompt?
Or does it just sit there forever w/no response?

Rgds,
Jeff

[TD Clark]

Users sit forever without a login.

[Jeff Schussele]

Well, you're going to want to get a glance session running BEFORE the bottleneck occurs, as you probably won't be able to get one going afterwards, to pinpoint just where the system is choking.

But let's start with your kernel parameters first. Attach an output of the kmtune command & we'll go from there. But be forewarned, a 2 CPU L can be brought to it's knees by a huge Oracle DB even when it's tuned properly.

Rgds,
Jeff

[doug hosking]

Are you running a trusted mode configuration?
If so, check out libsec patch PHCO_23422 before doing anything more drastic.