> I hear PETSc has some magic flag that lets it run multithreaded but I
> don't know how to turn that on.
Below is Matt's answer to my question. I guess I misunderstoof back then
how this is going to work, it isn't quite what I had in mind...
The link to the function he mentions is this:
ht
On Fri, 2008-01-25 at 11:14 -0600, Wolfgang Bangerth wrote:
> > The issue is that PETSc does everything on a per-MPI-process basis and, to
> > the best of my knowledge, does not use threads itself to implement e.g. its
> > matvec. And threaded BLAS will only take you so far... So you could
> > as
> The issue is that PETSc does everything on a per-MPI-process basis and, to
> the best of my knowledge, does not use threads itself to implement e.g. its
> matvec. And threaded BLAS will only take you so far... So you could
> assemble the system matrix with threads on 16 cores in a node, but wh
>> A lot of people (including myself) are still skeptical that it's even
>> a good idea. I personally think that the complexity involved in
>> creating MPISMP software outweighs any potential gains. MPI software
>> is hard to write... and so is SMP put the two together and you are
>> just ask
> A lot of people (including myself) are still skeptical that it's even
> a good idea. I personally think that the complexity involved in
> creating MPISMP software outweighs any potential gains. MPI software
> is hard to write... and so is SMP put the two together and you are
> just asking
On Jan 24, 2008 12:07 PM, Wolfgang Bangerth <[EMAIL PROTECTED]> wrote:
> > Along those lines, Derek, do you know about threading in Trilinos?
>
> I would be interested in hearing about that too.
I really don't know about threading and Trilinos... there have been
some investigations on whether or n
On Thu, 24 Jan 2008, Wolfgang Bangerth wrote:
>>> Now let's see what our friends from the competition have to say ;-)
>>
>> Competition? Does this mean you've added triangles, tets, prisms and
>> pyramids while we weren't looking? ;-)
>
> :-) I guess I could come up with other things instead ;-
> I'm actually quite interested in the answer to this question. Has *anyone*
> gotten PETSc working well inside a multithreaded program? It should be
> possible to call PETSc only from a single thread, but that kinda kills the
> point.
You can call it from several threads, but you have to synch
> > Now let's see what our friends from the competition have to say ;-)
>
> Competition? Does this mean you've added triangles, tets, prisms and
> pyramids while we weren't looking? ;-)
:-) I guess I could come up with other things instead ;-)
> libMesh does have hooks into matrix-free solve
> libMesh just hooks to PETSc and LASPACK for sparse linear algebra,
> whereas deal.II has its own multithreaded linear solvers (which IIRC
> were more efficient than PETSc?) for shared memory systems. If you're
> running on a four-core workstation, for example, I think deal.II only
> needs to sto
On Thu, 24 Jan 2008, Wolfgang Bangerth wrote:
> Now let's see what our friends from the competition have to say ;-)
Competition? Does this mean you've added triangles, tets, prisms and
pyramids while we weren't looking? ;-)
I think you've basically covered it - the biggest memory expenditure
> I am currently looking into designing a new 3D finite element
> geo-electric code. I have come across deal.II and libmesh. Both
> libraries look quite promising, each having their
> advantages/disadvantages. On the plus side deal.II supports Nedelec
> elements which I am quite interested in usin
12 matches
Mail list logo
