IDS Forum

Re: Physical CPU Statistics

Posted By: Art Kagel
Date: Monday, 5 October 2009, at 10:21 a.m.

In Response To: Re: Physical CPU Statistics (ANEES AHMAD)

I'm no Sun expert, but I know that it can be done. Some say you can use
psradm to disable the individual threads as processors except for the first
thread on each core (ie on an 8 thread/core Niagra II processor disable all
but 0, 8,, 16, etc.). But I would check with Sun to see if there is a more
direct way (IB that there is).

The problem is that the hardware threads are designed to efficiently run
traditional multi-threaded applications whose many threads perform a small
fast task then spend most of their time suspended waiting to coordinate with
other threads. IDS's threads, which BTW are NOT OS level threads but use a
proprietary IDS threading library, run until they have to block to wait for
some engine resource. That means that they run full out for, what to a
traditional mult-threaded application would seem like, a very long time
before relinquishing the processor to another thread within the IDS engine.
Note they even going from thread to thread, the OS and processors will see
a single OS level thread running full out non-stop for days at a time
sometimes. This does not work well on the Niagra processors with threading
enabled.

Art

Art S. Kagel
Oninit (www.oninit.com)
IIUG Board of Directors (art@iiug.org)

Disclaimer: Please keep in mind that my own opinions are my own opinions and
do not reflect on my employer, Oninit, the IIUG, nor any other organization
with which I am associated either explicitly or implicitly. Neither do
those opinions reflect those of other individuals affiliated with any entity
with which I am affiliated nor those of the entities themselves.

On Mon, Oct 5, 2009 at 2:44 AM, ANEES AHMAD <aanees@i2cinc.com> wrote:

> NO we are not facing performance issues actually. I just need to collect
> the
> stats that how the processoers thread are behaving so that load could be
> balanced for different instancess.
> I think that mpstat is a good command to collect such stats.
>
> Art, As you mentioned that one should turn off the hardware threads and
> treat
> the machine as a simple 6 core box.Can you please let us know that how the
> hardware threads could be turned off ???
>
>
>
> *******************************************************************************
> Forum Note: Use "Reply" to post a response in the discussion forum.
>
>

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Messages In This Thread

• Physical CPU Statistics
  ANEES AHMAD -- Wednesday, 30 September 2009, at 3:59 a.m.
  • Re: Physical CPU Statistics
    Art Kagel -- Wednesday, 30 September 2009, at 9:47 p.m.
    • Re: Physical CPU Statistics
      ANEES AHMAD -- Monday, 5 October 2009, at 2:44 a.m.
      • Re: Physical CPU Statistics
        Art Kagel -- Monday, 5 October 2009, at 10:21 a.m.
  • Re: Physical CPU Statistics
    Frank Langelage -- Sunday, 4 October 2009, at 5:33 p.m.

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