topic Re: SMP load balancing in Operating System - HP-UX

SMP load balancing

Timo J — Mon, 08 Mar 2004 08:33:27 GMT

We have a 4-CPU rp5470 running our application. Attached is the top output of the situation, when one of our processes (in fact, it's from third party) freaked out (fooProcess).

My question is that how is the load balancing between prosessors working in HP-UX SMP? If you take a look at the attached output, seems like CPU 3 is doing much more work than other processors. Due to that, our own application may fail to timeouts on socket handling (Yes, I know that our own application should work better ;| ). Is there anyway to balance the situation? Or in the other hand, is there really any need to balance that situation?

Re: SMP load balancing

Thayanidhi — Mon, 08 Mar 2004 09:39:27 GMT

Hi,

I think you go may for Process Resource
Manager(PRM) or Work Load Manager (WLM)
to allocate resources for processes.

TT

Re: SMP load balancing

Sundar_7 — Mon, 08 Mar 2004 11:32:55 GMT

You have something called processor sets with Process Resource Manager. You can use this to restict the application usage to a specific processor.

Workload manager works hand-in-hand with PRM and it is the only Goal based Work load management tool available in the market right now.

PRM is metric based workload management tool.

Re: SMP load balancing

Jeff Schussele — Mon, 08 Mar 2004 11:38:55 GMT

Hi Mikko,

It's not enough to just have multiple CPUs - the application MUST be written multi-threaded to use *more* than one CPU.
I suspect in your case the app is single-threaded & if so, it will *always* live on one & only one CPU when it starts up.

Rgds,
Jeff

Re: SMP load balancing

Timo J — Tue, 09 Mar 2004 00:55:46 GMT

Jeff,

the application is multi-threaded. Looks like we had to purchase that PRM.

Re: SMP load balancing

Shaikh Imran — Tue, 09 Mar 2004 01:01:08 GMT

Hi,
Is this the same situation always when u do top i.e. always does the foo process goes to only one cpu an choke it ?
If yes then your process is a single thread one but as far as SMP in HP is concerned it is always balanced between the resources.
You can also use glance plus for more information and benchmarks.

Regards,