[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-gsl] Question about GSL performance under OpenMP

From: Brian Hawkins
Subject: Re: [Help-gsl] Question about GSL performance under OpenMP
Date: Thu, 6 Oct 2011 09:46:34 -0700

Hi Pedro,

In my experience the design of GSL is very amenable to parallelism, and I
would be quite surprised if it was causing problems.

However, it's pretty common to scale up a program to n threads and get less
than a factor of n speed up.  It depends a lot on what the code is doing and
what kind of hardware you've got.  There are also some issues related to
OpenMP threading itself.  A quick guess is that maybe some of your equations
solve much faster than others, so you might want to add "schedule(dynamic)"
to the pragma before your loop.


On Thu, Oct 6, 2011 at 9:00 AM, <address@hidden> wrote:
> Date: Wed, 5 Oct 2011 18:20:38 -0700
> From: Pedro Gardete <address@hidden>
> Hi,
> I need to go through many systems of equations, which I'm using
> the gsl_multiroot_fsolver_hybrid method to solve for. The systems solve
> fine, but when I put them inside an OpenMP loop (each thread solves one
> system at a time and stores the result) the performance invariably comes
> down for each thread as I add more. Should this be expected given that the
> threads are independent (ie, don't wait for each other)?
> Thanks,
> Pedro

reply via email to

[Prev in Thread] Current Thread [Next in Thread]