RAMDISK for ABAQUS STANDARD

[biofriend]

Hi
Dear Dr. Jorgen,

I run ABAQUS/Standard in a combination of *Visco and *Static on a xp professional , core 2 duo 2.5Ghz with 3Gbs of Ram notebook.

The Abaqus , procedure however, does not use more than 1/3 to 1/2 of the availablee Ram and seems to prefer to write on HDD.Although I have chosen the maximum physical memory usage for it(100% and even it works with 150% when I choose the memory item by percentage).

Therefore i decided to use a Ramdisk(virtual drive out of ram memory which is said to be times faster than HDD in I/O procedures). to write and read scratch files, and added scratch='ramdisk directory' to abqus_v6.env at site folder.

But the procedure runtime didn't show a great difference than when this was in default setting. Also the scratch files were about 2 Mbs and not so huge to be meaningful I think.
Are there other intermediate files that if are located on ramdisk,make the /standard runtime shorter? How do you find the idea that I have used?


Thanks a lot for your concern,
Yours
Biofriend

[Jorgen]

I have not tried to run Abaqus in ramdisk. It sounds like a cool idea though. I an not sure, however, how many simulations are limited by harddisk read/write. Let us know what performance you get.

Note that for Windows PCs, some temporary files are stored in a directory like:
~/jorgen/Local Settings/Temp/

-Jorgen

[biofriend]

Thanks Jorgen,


Yes , as you said, scratch files are written in a temp folder like ~\Documents and Settings\Max\Local Settings\Temp by default and I made these files to be recorded on a virtual drive on ram memory which is expected to be much faster; nothing really changed!

I tried to do same things on windows xp 64 bit , with 1 more GB of ram , again no improvement and everything exactly the same!

I also made the working directory to be on that ram space(DAT and ODB parts).

The thing which keeps me so curious is that, a part of my cpu and a good part of ram is always free but standard keeps on writing on HDD! I really wonder what is going on inside the abaqus between each two increments (the CPU usage history oscillates and HDD led shows working,alternatively)

Thank you very much,
Please let me know if you had any idea about this, It will be much appreciated,

Yours Sincerely

[biofriend]

Hi

With Filemon soft. I found out that Abaqus/Standard continuously tries to write add to ODB file which keeps the HDD busy and apparentlt slows down the system. This happens despite my observation that CPU and Ram seem NOT to be full. Why this happens? is there a way to get rid of this real time writing of Abaqus on hard disk?


Many Thanks,

[biofriend]

Hi Dr. Jorgen,

I tried to configure and use the ramdisk again. It was a relative satisfaction cause in this way I have ODB on the ram and my HDD does not work all the time which is beneficial both for HDD life and may be for procedure speed,

I thought this might be of interest to you,

Sincerely

[Jorgen]

Sounds very good. If you notice any significant speed improvements, please let us know...

-Jorgen