Subject: NONMEM and Windows NT.
Date: 21 Nov 1997 03:57:10 -0500

Dear NONMEM users:

I would appreciate any information regarding your experience running NONMEM in a Windows NT environment with dual processors. I am particularly interested in how one would designate each processor to perform separate NONMEM runs?

Thank you,
Jim Lane, Pharm.D.


Subject: RE: NONMEM and Windows NT.
Date: 21 Nov 1997 16:09:29 -0500

Jim -

I'm running NONMEM on an HP Vectra XU6/200 with dual-Pentium Pro 200 MHz processors and 160 Mb memory. I've been so pleased with the performance of this hardware that I setup similar PC's for two other scientists in my group.

When you install NT, it will detect a multiprocessor situation and automatically install the proper drivers, etc. If you upgrade a single processor machine to a multiprocessor machine, you'll have to do the NT update manually.

Overall, I think that running NONMEM on a dual-processor PC is the best environment if you are going to be using a PC. Often times, I will have a NONMEM run going while I'm working on document prep, email, etc. What happens internally is that NONMEM will use 100% of a processor (you can see what is going on with the processors, memory etc. using the Windows NT Task Manager) and leave the second processor free for other things. If you want to run a second NONMEM job, the free processor will now be 100% devoted to that NONMEM job. After that, any more applications that are run, including additional NONMEM jobs will compete for processor time and cause NONMEM run times to increase accordingly and the other additional applications will be a little slower in responding.

Please note that having dual-processors will not decrease the time of a NONMEM run compared to a uniprocessor machine; you can just continue to use your PC for other applications at the same time. NONMEM is not a multithreaded application so it will not be run on two processors simultaneously.

Let me know if you have any other questions or if I can be of any help.

Best Wishes,
John P. Sabo
Senior Scientist
Boehringer Ingelheim Pharmaceuticals, Inc.
Ridgefield, CT
Tele: 203-798-5355


From: "Steven L. Shafer" <>
Subject: Multiprocessor PC
Date: 21 Nov 1997 22:48:05 -0500

I've been running NONMEM on a multiprocessor PC (dual Pentium Pro 200) for about a year now, and it works marvelously, as Dr. Sabo states. If you write your own PREDs, and these have big loops to process, then you can utilize the multiprocessing ability within your PRED routine by setting up multiple threads. Win NT is happy to run these on separate processors, and will do it automatically. The tools for synchronizing the threads aren't difficult to set up. However, I wouldn't recommend getting into the NONMEM code proper, although there are probably many areas that would could be run on dual processors, because probably only Stu Beal understands it well enough to deal with the timing subtleties.

Steve Shafer


From: Nick Holford <>
Subject: Re: Multiprocessor PC, NT, pcANYWHERE
Date: 23 Nov 1997 00:23:13 -0500

We have been running NONMEM with a dual pentium II 233 Mz PC under NT 4.0 (Watcom f77 v 10.6). We use the machine as a computation server and have 2 NONMEM jobs running simultaneously most of the time. We can control the machine using pcANYWHERE (we use v 8.0) with a TCP/IP connection directly from a machine on our LAN or with a 33.6 k modem via PPP.

The dual pentium is a cost effective way to do computation because we only need one hard drive, one ethernet card, one video board etc. We do have 64 MB RAM while out single CPU machines (Win 95) have only 32 MB. With 2 NONMEM (v 5.0) jobs running on the dual pentium NT machine we still have about 15 MB of RAM free according to the task manager.

Nick Holford, Dept Pharmacology & Clinical Pharmacology
University of Auckland, Private Bag 92019, Auckland, New Zealand tel:+64(9)373-7599x6730 fax:373-7556