Dual CPU problem?

Dual CPU problem?

Post by Andy Tucke » Wed, 31 Jul 1996 04:00:00




> But the RT scheduler just got implemented in 2.4. So 2.3 and 2.2
> does not apply

Eh?  The RT scheduler was implemented in 2.0.  The basic mechanism
is part of SVR4.  Look at "Realtime Scheduling in SunOS 5.0" at
http://www.sun.com/developer-products/sig/threads/papers/rt_sched.ps
or read the summary in "UNIX Internals" by Uresh Vahalia.

And RT scheduling has nothing to do with the cache affinity
scheduling we were talking about, which was implemented in 2.2
(but has not been described in detail in any publications I know of).

--
Andy Tucker

Solaris Kernel Development
I speak only for myself, not SunSoft or Sun Microsystems.

 
 
 

Dual CPU problem?

Post by Ling Wan » Wed, 31 Jul 1996 04:00:00






> > > >On 4.1.3
> > > >SS10-40/51/61 gave consistent numbers of ~12/50/60mflops
> > > >SS10-512 Gave wildly varying numbers of ~12-45mflops

> > > If the SS10-512 numbers are from 4.1.3 as well (it's hard to tell for sure
> > > what you meant above), I'm hardly surprised.

> > The original thread is about SunOS and multiprocessing

> Actually, the original post referred to Solaris 2.5 (SunOS 5.5).

> > And I said SunOS with multiple CPU's might even
> > be slower because the round robin scheduler does not
> > send a process to it's last exec'd CPU in order to
> > preserve the cached data from there.

> True for SunOS 4.x, not for 5.x.

So where can I find papers on solaris' implementation?
Quote:

> > > Try it on Solaris 2.5.1 and see what happens.

> > I read some antique usenix with a paper by some sun guy
> > talking about different impletementations of the scheduler
> > besides the round robin method.  I am surprised it
> > took sun that long to actually implement it.

> It was implemented long ago.  Try 2.3 if you prefer, or 2.2 if you
> can find a system still running it.

But the RT scheduler just got implemented in 2.4. So 2.3 and 2.2
does not apply

 
 
 

Dual CPU problem?

Post by Alan L. Stang » Wed, 31 Jul 1996 04:00:00




> > Post the code!  Let's do some tests.

> Write your own.
> how hard is it to write:

> Iterate thru 10k-2M
>  Allocate the memory
>   Do some CPU ops with that memory X times
>  end
> end

> Anyway.  Now I only have solaris, so a compiler is not readily
> available to compile anything.

Duhhh.  You're the guy complaining about the scheduler.  Post your
code so we can see what you're talking about.

For a compiler, you can download gcc from lots of places.
See ftp://ftp.ccd.bnl.gov/pub/software/SunOS5

Cheers,

--

 
 
 

Dual CPU problem?

Post by Ling Wan » Thu, 01 Aug 1996 04:00:00





> > > Post the code!  Let's do some tests.

> > Write your own.
> > how hard is it to write:

> > Iterate thru 10k-2M
> >  Allocate the memory
> >   Do some CPU ops with that memory X times
> >  end
> > end

> > Anyway.  Now I only have solaris, so a compiler is not readily
> > available to compile anything.

> Duhhh.  You're the guy complaining about the scheduler.  Post your
> code so we can see what you're talking about.

I wrote the code 3 jobs ago, when I still remembered C.

Quote:

> For a compiler, you can download gcc from lots of places.
> See ftp://ftp.ccd.bnl.gov/pub/software/SunOS5

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