Why is Patran taking forever to attach my op2 file?

I just did a fresh install of Patran 2017. I am running a 3e6 dof line sol101 model that runs in 8 minutes and produces an op2 file that is 5.9GB in size. It takes over 2 hours to attache the op2 in Patran. Once attached then I can do my post processing. Then if I exit from Patran and then start patran again with the same attached file I have to wait another 2 hours for the first fringe plot. Please give me a clue how to fix this. This makes Patran 2017 unusable. I do not recall having this type of problem with Patran 2014. I have 64GB of RAM and I think I have default settings for Patran and Nastran.

0 toby.t.norris over 6 years ago

Please don't tell me to just use the new H5 format. I did try that and yes it does work much better with attach time of less than a minute. However, for some reason the h5 format does not include the load case name for my many subcases. I just have SC01, SC02, etc. I need all those subcase names because the subcase name shows up on the plots and without the subcase name coming in on the h5 file I am forced to try and rename all my subcases manually in Patran or via PCL. As you can imagine this is a nightmare if you have hundreds of subcases. The op2 format does include the subcase names and so that is why I need it.
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0 karlR over 6 years ago

Looks like a swapping issue, can be changed with the PDB_C_CACHE_SIZE variable

Assuming you run Patran on Windows, I recommend to create a file “user_setup.pm” in your user home directory containing these lines:

# ---PDB_C_CACHE_SIZE = 50% of RAM

setEnv('PDB_C_CACHE_SIZE','32000000000');

# set Nastran mem for attach op2, attach master and 2013ff nastran file import, max. 8GB.

setEnv('DRANAS_NAST_MEM','2GB', 'OverWrite');

# set Nastran SDIR and DBS for attach op2 and attach master, nifimp since 2013.

# to a fast partition, here c:\scrach

setEnv('TMP', 'c:\scratch', 'OverWrite');
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0 toby.t.norris over 6 years ago

Thanks very much for that suggestion. I will definitely give that a try and put that file into my Windows 7 home directory. I was hoping that there was something I could add to my p3midilog.sys or p3epilog.sys files to fix this problem. I did not know about the option of using a user_setup.pm file.

UPDATE:

That user_setup.pm file apparently had absolutely no effect. When I open my db file that has was previously attached to this large op2 file the program litterly freezes for an hour doing nothing except for the following process:

"c:\appl\msc\patran_x64\20170\mscnastran_files\20171\servermode\msc20171\win64i4\analysis.exe FPE=yes"

I cannot imagine what is going on and why patran cannot simply open my db file once it has been attached to an op2 file that is 5.9 GB in size. Eventually after the long long long wait and an infinite amount of patience on my part, the db file is opened and Patran works normally. It is amazing to me that it takes far longer to attach the op2 file or open a db with an attached op2 than it does to do the nastran run in the first place.

Do you have any other suggestions, or should I create a support ticket?
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