View previous topic :: View next topic |
Author |
Message |
mjhynes
Joined: 30 May 2006 Posts: 8
|
Posted: Mon Jul 28, 2008 3:43 pm Post subject: core duo problems |
|
|
I have updated by WinEQNMR programs using Winteracter and Salford Fortran 5.00.2195.6601.
I developed the software on my Dell Optiplex GX270 and everything runs fine. I have also put it up on a couple of other single processor machines and all runs as it should.
However, when I try to run the software on a Dell Optiplex 755 with a core duo processor, the program runs at a snails pace, around 1% as fast as on the GX270 or not at all.
Examination of the task manager shows two version of the process running.
Obviously, I need to change the compiler options.
Any suggestions as to what I must do.
I need a solution urgently.
mjhynes |
|
Back to top |
|
|
DanRRight
Joined: 10 Mar 2008 Posts: 2818 Location: South Pole, Antarctica
|
Posted: Mon Jul 28, 2008 11:40 pm Post subject: |
|
|
Wow! Probably this Dell 755 was built in Chernobyl. Then it mutated into dualcore My computer also gave me headache last week, though I have to admit it is overclocked to the limit, seems memory was fried and started to degrade.
But I've never heard something like that. There is no difference in compiling options for single core or multicore, I use and switch between them all the time. Mutation can be caused by the external library, as a free guiess. Like Winteracter. But nobody can tell that now for sure with such crazy bug. BTW, why did you choose Winteracter and not a Clearwin+ ? |
|
Back to top |
|
|
BILLDOWS
Joined: 22 Jul 2005 Posts: 86 Location: Swansea, UK
|
Posted: Wed Jul 30, 2008 11:57 am Post subject: |
|
|
I have in the last month moved over to an identical Optiplex 755 machine with Vista - just using FTN95 - latest version - and have have no speed problems at all. Just works very fast. Can now run 2 runs side by side with no speed degradation.
Sorry I cannot help.
Bill |
|
Back to top |
|
|
LitusSaxonicum
Joined: 23 Aug 2005 Posts: 2388 Location: Yateley, Hants, UK
|
Posted: Wed Jul 30, 2008 3:24 pm Post subject: |
|
|
In Windows Task Manager, select the Processes tab. Find the program. Right click on it and examine the setting under Set Priority. (This is based on XP, Vista may be slightly different). My guess is that you are running at low priority.
My experience is that selecting the highest priority runs the program on one cpu core only. The next setting down is possibly faster on a multicore machine.
I have no idea how to get this setting from Fortran, but it must be possible.
You can get a free download (30 days trial?) of a program Prio that makes the priority setting "persistent" from here:
http://www.prnwatch.com/prio.html
which adds a setting to the Task Manager that always selects the priority you want for your application.
An alternative is a program called Process Lasso - see here:
http://www.bitsum.com/prolasso.php
It seems sensible to turn down the priority on everything else if you have a long-running Fortran program, and to turn it all back up on completion. In the meantime, your program needs the highest possible settings.
Eddie |
|
Back to top |
|
|
|