NONMEM Users Network Archive

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Re: NONMEM memory vs. run time

From: Nick Holford <n.holford>
Date: Mon, 08 Sep 2008 11:12:29 -0400

Leonid, Darin,

Here are some experimental results rather than theoretical predictions.
I ran a problem (ADVAN6) with two 'sizes' of NONMEM created with NMQUAL
using Wings for NONMEM. The 'std' size is the default NONMEM
configuration. The '570' size is close to the 'big' version provided
with NMQUAL. I ran the problems with an Intel core duo processor with 1
Gb RAM compiled with Intel Fortran version 10.1024. I used NONMEM VI 2.0
installed with NMQUAL-6.3.2 and Windows XP.
 
I tried each size of problem two times. Run times exclude NM-TRAN and
the compile/link step. You will see that the bigger NONMEM size took 5%
longer to complete. There were no page faults visible with the Task
Manager using either size.
std =Mem Usage 51.1 M byte VM Size 97.1 Mbyte Runtimes: 80.88
sec/ 81.82 sec
570=Mem Usage 199.8 M byte VM Size 1107.9 Mbyte Runtimes: 84.10
sec/ 87.22 sec

These results are similar to those I have observed before. The bigger
versions of NONMEM run more slowly. This is why I prefer to match the
NONMEM size to the problem size. For smaller problems (fewer parameter,
fewer obs/subject) I use the std size. For bigger problems WFN allows a
choice to increase either parameters, obs/subject or both.

Nick

Darin Perusich wrote:
> The increase in memory consumption doesn't impact runtime positively
> or negatively, unless of course your system doesn't have enough
> physical memory to accommodate the increase. NONMEM's memory footprint
> is directly related to the buffer values in the SIZES file, as you
> increase the values the memory footprint increases to accommodate.
>
> In the end processor speed is really the only thing that positively or
> negatively effects NONMEM runtime.
>
> Leonid Gibiansky wrote:
>> Dear All,
>> I noticed that the Nonmem installed with NMQUAL "big nm6" defaults
>> instead of the standard ones results in approximately 10-times increase
>> in the memory required to run Nonmem (on my recent problem, from 12 MB
>> to 140 MB). I am wondering whether anybody checked how this influences
>> the run time. Is it better (in terms of the run time) to use standard
>> sizes, or "big" is OK if you have enough RAM?
>> Thanks!
>> Leonid
>>
>

--
Nick Holford, Dept Pharmacology & Clinical Pharmacology
University of Auckland, 85 Park Rd, Private Bag 92019, Auckland, New Zealand
n.holford
http://www.fmhs.auckland.ac.nz/sms/pharmacology/holford
Received on Mon Sep 08 2008 - 11:12:29 EDT

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