Hello,
I'm trying to improve the parallel efficiency of gmres solve in my. In my
CFD solver, Petsc gmres is used to solve the linear system generated by the
Newton's method. To test its efficiency, I started with a very simple
inviscid subsonic 3D flow as the first testcase. The parallel
Hi Matt,
Thanks for your suggestions. Here is the output from Stream test on one
node which has 20 cores. I run it up to 20. Attached are the dumped output
with your suggested options. Really appreciate your help!!!
Number of MPI processes 1
Function Rate (MB/s)
Copy: 13816.9372
On 24 Jun 2015, at 17:02, Asbjørn Nilsen Riseth ris...@maths.ox.ac.uk wrote:
Hi all,
I'm currently trying to set up a nonlinear solver that uses NGMRES with
NEWTONLS as a right preconditioner. The NEWTONLS has a custom linear
preconditioner. Everything is accessed through petsc4py.
Hi Justin,
I don't see anything obviously wrong that would be causing this variation
in iterations due to number of processors. Is it at all feasible to send be
an example code that reproduces the problem (perhaps a smaller version)?
I'm still guessing the problem lies in numerical precision, it
Jason,
I was experimenting with some smaller steady-state problems and I still get
the same issue: every time I run the same problem on the same number of
processors the number of iterations differs but the solutions remain the
same. I think this is the root to why I get such erratic behavior in
On Jun 25, 2015, at 3:48 PM, Lei Shi stonesz...@gmail.com wrote:
Hi Justin,
Thanks for your suggestion. I will test it asap.
Another thing confusing me is the wclock time with 2 cores is almost the same
as the serial run when I use asm with sub_ksp_type gmres and ilu0 on
On Jun 25, 2015, at 9:25 PM, Lei Shi stonesz...@gmail.com wrote:
Barry,
Thanks a lot for your reply. Your explanation helps me understand my test
results. So In this case, to compute the speedup for a strong scalability
test, I should use the the wall clock time with multiple cores as
Run with -ts_view -log_summary and send the output. This will tell the
current solvers and where the time is being spent.
Barry
On Jun 25, 2015, at 6:37 PM, Li, Xinya xinya...@pnnl.gov wrote:
Dear Sir,
I am using the ts solver to solve a set of ODE and DAE. The Jacobian matrix
is
