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  1. Old Comment

    Advanced tips for working with the OpenFOAM shell environment

    I want to open a terminal without sourcing OpenFoam's bashrc. What should I do?
    I have tried bash --norc , $ bash --noprofile --norc and env -i bash --rcfile /etc/profile, but non of them worked
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    Posted January 31, 2019 at 18:02 by Samsam2 Samsam2 is offline
  2. Old Comment

    A few thoughts about today's CPU era...

    As I was revising what I wrote, I began rethinking what I read at https://en.wikipedia.org/wiki/Eighth...les#Comparison - for the PS4 memory specs, and I quote:
    Quote:
    • Original PS4:
      • 8 GB GDDR5 RAM @ 1375 MHz (5500 MHz effective) (176.0 GB/s)
      • 4.5–5.5 GB (flexible memory) available for games
    • PS4 Pro
      • 8 GB GDDR5 RAM @ 1700 MHz (6800 MHz effective) (217.6 GB/s)
    Which means that GDDR5 is being used as a 4 channel group... at least here...

    But then I look at the wikipedia page for GDDR5: https://en.wikipedia.org/wiki/GDDR5_SDRAM - and they mention:
    Quote:
    Hynix 40 nm class "2 Gb" (2 × 1024ł bit) GDDR5 was released in 2010. It operates at 7 GHz effective clock-speed and processes up to 28 GB/s. "2 Gb" GDDR5 memory chips will enable graphics cards with 2 GB or more of onboard memory with 224 GB/s or higher peak bandwidth.
    But after reading the initial introduction section, it looks like what the clocks are in fact the addition of 3 clocks:
    • 1x Command Clock CK at 1.25 or 1.375 GHz
    • 2x Write Clock WCK at 2.5 ot 2.75 GHz (each)
    So becoming:
    • 2.5×2+1.25 = 6.25 GHz
    • 1.375+2×2.75 = 6.875 GHz
    OK... so... it's in fact 3 channels? But the specs on the PS4 implies 4 channels...





    Anyway, if my understanding of this is correct, then the 6-8 GHz specs that the GPU cards keep advertising aren't all that great, when compared to the 8x2.6GHz that the EPYC CPUs have nowadays...


    But still, having RAM embedded into the motherboard or on a stacked die would allegedly reduce latency by quite a bit, as in graphics cards...
    permalink
    Posted January 6, 2019 at 17:01 by wyldckat wyldckat is offline
  3. Old Comment
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    Posted August 24, 2018 at 18:08 by wyldckat wyldckat is offline
  4. Old Comment
    Evren Linda's Avatar

    Rants removed from a recent post of mine about OpenFOAM vs OpenFOAM+ in 2016-02-14

    Your first post on OpenFOAM was: post #113 in January 14th, 2009

    Today 21 April 2018 you have a reputation power: 113!
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    Posted April 20, 2018 at 20:04 by Evren Linda Evren Linda is offline
  5. Old Comment

    Notes about running OpenFOAM in parallel

    Since I've already hit the 10000 characters limit on the main blog post:
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    Posted April 8, 2018 at 15:45 by wyldckat wyldckat is offline
  6. Old Comment

    Linking dynamic libraries and initializing variables

    I haven't confirmed this yet, but several months ago, this might have been somewhat fixed in OpenFOAM 3... namely in these commits:
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    Posted June 25, 2017 at 12:34 by wyldckat wyldckat is offline
  7. Old Comment

    Notes about running OpenFOAM in parallel

    Yet another solution for the error message:
    Code:
      opal_shmem_base_select failed
      --> Returned value -1 instead of OPAL_SUCCESS
    Is given in the following posts:
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    Posted June 4, 2017 at 21:14 by wyldckat wyldckat is offline
  8. Old Comment

    Read this before emailing/PM me

    great job bruno sir

    you are one of a kind. a walking talking and hadcore debugging LEGEND.....what would this forum do without you???
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    Posted May 26, 2017 at 20:00 by saddy saddy is offline
  9. Old Comment
    alia's Avatar

    Notes about running OpenFOAM in parallel

    Quote:
    Originally Posted by wyldckat View Comment
    Hi Ali,


    For fsiFoam, you need to contact the current author, Željko Tuković. Because as far as I know, running in parallel is not yet fully implemented, not even in the latest source package for foam-extend 4.0, that is provided here: https://openfoamwiki.net/index.php/E...re_interaction

    If you have figured out how to run those solvers in parallel, feel free to edit that wiki page and add a section for it.

    As for running in parallel in general, feel free to start the wiki page https://openfoamwiki.net/index.php/H...un_In_Parallel

    Best regards,
    Bruno
    Thank you Bruno!
    permalink
    Posted April 10, 2017 at 07:55 by alia alia is offline
  10. Old Comment

    Notes about running OpenFOAM in parallel

    Hi Ali,

    Quote:
    Originally Posted by alia View Comment
    I'm particularly interested in application of parallel computation in FsiFoam.
    For fsiFoam, you need to contact the current author, Željko Tuković. Because as far as I know, running in parallel is not yet fully implemented, not even in the latest source package for foam-extend 4.0, that is provided here: https://openfoamwiki.net/index.php/E...re_interaction

    If you have figured out how to run those solvers in parallel, feel free to edit that wiki page and add a section for it.

    As for running in parallel in general, feel free to start the wiki page https://openfoamwiki.net/index.php/H...un_In_Parallel

    Best regards,
    Bruno
    permalink
    Posted April 8, 2017 at 08:39 by wyldckat wyldckat is offline
  11. Old Comment
    alia's Avatar

    Notes about running OpenFOAM in parallel

    Hi Bruno! I am working with OpenFOAM for three years somehow a newcomer . I would like to participate in documentation of parallelization in OpenFOAM. I'm particularly interested in application of parallel computation in FsiFoam.
    Regards,
    Ali
    permalink
    Posted April 7, 2017 at 13:13 by alia alia is offline
  12. Old Comment

    Notes about running OpenFOAM in parallel

    Another one, as a reminder for selecting any other MPI versions based on module load: https://www.cfd-online.com/Forums/op...fic-linux.html
    permalink
    Posted December 22, 2016 at 11:15 by wyldckat wyldckat is offline
  13. Old Comment
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    Posted May 1, 2016 at 20:11 by wyldckat wyldckat is offline
  14. Old Comment

    Blog about my forks at github for the repositories OpenFOAM and ThirdParty

    Instead of editing the blog post and tampering with the historic dates mechanism, I've decided to write a comment instead, on the status of this line of thinking.
    Essentially, I started dealing with so many repositories and trying to help so many people on the forum, that writing on blog format sort-of became obsolete.

    Nonetheless, I still do have a blog of sorts and is maintained here: http://wyldckat.github.io - although it currently points to the wiki for the same project, since it's easier for me to edit locally and git commit+push: https://github.com/wyldckat/wyldckat.github.io/wiki

    Either way, I haven't been doing as many forks and have been contributing more directly to projects, therefore any breadcrumbs on what I do are mostly kept on their respective bug/issue trackers, repositories and project pages.
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    Posted January 9, 2016 at 10:41 by wyldckat wyldckat is offline
  15. Old Comment

    Notes about running OpenFOAM in parallel

    And another link: http://www.cfd-online.com/Forums/ope...m-2-3-1-a.html - neat solutions for SSH issues with Open-MPI newer than 1.6.5
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    Posted January 6, 2016 at 18:30 by wyldckat wyldckat is offline
  16. Old Comment

    Notes about running OpenFOAM in parallel

    OK... I've hit the limit of 10000 characters on this blog post... I'm going to have to move this to a wiki page sometime soon... Anyone would like to help?

    By the way, the link for the document by Shannon Keough was sent me by our fellow forum member KateEisenhower: http://www.cfd-online.com/Forums/ope...mulations.html
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    Posted October 31, 2015 at 09:28 by wyldckat wyldckat is offline
  17. Old Comment

    Running OpenFOAM in parallel with different locations for each process

    Hi katakgoreng,

    Quote:
    Originally Posted by katakgoreng View Comment
    I suspect OpenFoam will replace $TMPDIR for each roots with path of the master node only (as the application starts on master node). Is there a way to check if the OpenFoam is using the correct distributed storage?
    The application decomposePar is only used in the master node, therefore it will only use the local temporary folder location.
    In order to use the temporary folder for a specific node (machine), then you'll have to first ask that node (machine) what is the path it's using for a temporary folder.

    Best regards,
    Bruno
    permalink
    Posted February 1, 2015 at 18:06 by wyldckat wyldckat is offline
  18. Old Comment

    Running OpenFOAM in parallel with different locations for each process

    Hi Bruno,

    For parallel OpenFoam run with distributed storage, does the roots need to be absolute path?
    If the local temporary scratch disk for each node was set to an environmental variables "$TMPDIR" (same name but different location), can it be used in the decomposeParDict as follows,

    distributed yes;
    roots (
    "$TMPDIR"
    "$TMPDIR"
    "$TMPDIR"
    );

    I suspect OpenFoam will replace $TMPDIR for each roots with path of the master node only (as the application starts on master node). Is there a way to check if the OpenFoam is using the correct distributed storage?
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    Posted February 1, 2015 at 17:46 by katakgoreng katakgoreng is offline
  19. Old Comment

    Building Code Documentation on OpenFOAM 2.0.0/x

    Hi zcarral,

    Quote:
    Originally Posted by zcarral View Comment
    But I do not see the OpenFOAM documentation? Where is it created?
    Mmm... back then I forgot to give the generic command that indicates the folder where it is located.
    Running the following command will give you the complete path to the main HTML file "index.html":
    Code:
    echo $WM_PROJECT_DIR/doc/Doxygen/html/index.html
    Best regards,
    Bruno
    permalink
    Posted August 30, 2014 at 09:17 by wyldckat wyldckat is offline
  20. Old Comment

    Building Code Documentation on OpenFOAM 2.0.0/x

    Dear Bruno,

    I do not understand well the procedure to obtain the OpenFOAM documentation. I did the following steps in Ubuntu:

    sudo apt-get install doxygen
    sudo su -c "$WM_PROJECT_DIR/bin/foamExec ./Allwmake > docmake.log 2>&1"

    But I do not see the OpenFOAM documentation? Where is it created?
    permalink
    Posted August 21, 2014 at 07:20 by zcarral zcarral is offline

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