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<div><span style="color:rgb(33,33,33);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:14px;letter-spacing:0.2px">Myriam,</span><br>
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<div>Do you have 'execution time scalability' plot? Did you use '-mat_freeintermediatedatastructures' for PETSc 3.10.2?</div>
<div>We made several computing optimizations on MatPtAP(), which might trade memory for speed. It would be helpful to see a complete comparison.</div>
<div>Hong</div>
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<div dir="ltr" class="gmail_attr">On Tue, Apr 9, 2019 at 7:43 AM Myriam Peyrounette via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>> wrote:<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Hi,<br>
<br>
in my first mail, I provided a memory scaling concerning the PETSc<br>
example #42. You'll find attached the main files used (one for PETSc<br>
3.6.4, one for PETSc 3.10.2), and the corresponding memory scaling.<br>
<br>
In the main files, I modified the solver/preconditioner, so that it<br>
corresponds to my problem. You'll find the modifications by searching<br>
the keyword "TopBridge". In particular, I use GAMG.<br>
<br>
Note that the example is about solving Stokes equation, so using GAMG<br>
may not be adapted. However, the memory gap appears and that's the<br>
point. No matter if the results are correct.<br>
<br>
Are these scripts useful for you? Let me know.<br>
<br>
Thanks,<br>
<br>
Myriam<br>
<br>
<br>
Le 04/04/19 à 00:09, Jed Brown a écrit :<br>
> Myriam Peyrounette via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>> writes:<br>
><br>
>> Hi all,<br>
>><br>
>> for your information, you'll find attached the comparison of the weak<br>
>> memory scalings when using :<br>
>><br>
>> - PETSc 3.6.4 (reference)<br>
>> - PETSc 3.10.4 without specific options<br>
>> - PETSc 3.10.4 with the three scalability options you mentionned<br>
>><br>
>> Using the scalability options does improve the memory scaling. However,<br>
>> the 3.6 version still has a better one...<br>
> Yes, this still looks significant. Is this an effect we can still<br>
> reproduce with a PETSc example and/or using a memory profiler (such as<br>
> massif or gperftools)? I think it's important for us to narrow down<br>
> what causes this difference (looks like almost 2x on your 1e8 problem<br>
> size) so we can fix.<br>
<br>
-- <br>
Myriam Peyrounette<br>
CNRS/IDRIS - HLST<br>
--<br>
<br>
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