processor choice

3 messages 3 people Latest: Nov 22, 2005

processor choice

From: Bill Knebel Date: November 21, 2005 technical
From: Bill Knebel billk@metrumrg.com Subject: [NMusers] processor choice Date: Mon, 21 Nov 2005 16:18:41 -0500 A few years ago there was a thread about benchmarking results for NONMEM across a number of different processors and systems ( http://cognigencorp.com/nonmem/nm/98apr292002.html). Given the relatively recent release of dual core processors I wanted to know if anybody has compared NONMEM runs on a dual processor machine to NONMEM runs on a dual core CPU. Assumming you were running two jobs simultaneously, I would be interested if anybody has seen any speed (runtime) increase or decrease with either setup. Bill -- Bill Knebel, PharmD, Ph.D. Principal Scientist Metrum Research Group 2 Tunxis Road Suite 112 Tariffville, CT 06081 email: billk@metrumrg.com tel: (860) 930-1370

Re: processor choice

From: Darin Perusich Date: November 22, 2005 technical
From: Darin Perusich Darin.Perusich@cognigencorp.com Subject: Re: [NMusers] processor choice Date: Tue, 22 Nov 2005 08:41:48 -0500 for an application to take advangate of a dual core cpu, much like pentium4's hyper-threading it needs to be a multithreaded and nonmem is about the furtherest thing from multithreaded. i did some runtime comparisons on single cpu P4 systems with HT (hyper-threading) enabled and disable, and dual cpu P4 systems with HT disabled. HT'ing doesn't by you anything when running nonmem other then a longer runtimes when you try to run a job/cpu. take a job that runs in 40 minutes single cpu with HT disable. when HT is enable and 2 identical jobs are run, one per virtual cpu the jobs take nearly twice as long. though runtime is marginally better with HT then when running 2 jobs when HT is disabled. when run on a dual-cpu system with HT disabled of the same speed, the 2 jobs run in the same time as a single job when HT is disabled. i can purchase a machine with dual 3.0GHz Intel Xeon processors for $1779.00, a dual-core 3.0GHz intel pentium D runs about $1707.00, or a singe 3.0GHz P4 for around $1550.00. if your goal is the maximize the number of nonmem jobs you can run in the shortest amount of time your better for going with dual processor machines any day. my 2 cents. -- Darin Perusich Unix Systems Administrator Cognigen Corp. darinper@cognigencorp.com

Re: processor choice

From: Mark Sale Date: November 22, 2005 technical
From: mark.e.sale@gsk.com Subject: Re: [NMusers] processor choice Date: Tue, 22 Nov 2005 09:14:45 -0500 Darin is correct, NONMEM is single threaded. Even if it were multi threaded, it probably couldn't take advantage of hyperthreading, as the super scalar architecture of Intel and AMD chips provides multiple instruction paths for integer operations only (aimed at gamers, they seem to outnumber us). NONMEM is (almost) entirely floating point. Dual core will multi thread very nicely (even for floating point operations), but that doesn't help a single NONMEM run. But, as Darin points out, you do essentially get two processors, so you can run two models without loss of performance. For those interested, a parallelized version of NONMEM may be available at some point, which would run twice as fast on a dual core (4 times as fast on a dual processor/dual core and potentially 100 times as fast in a data center with many processors) See abstract from AAPS ( http://abstracts.aapspharmaceutica.com/ExpoAAPS05/CC/forms/attendee/index.aspx?content=sessionInfo&sessionId=1715) Mark Sale M.D. Global Director, Research Modeling and Simulation GlaxoSmithKline 919-483-1808 Mobile 919-522-6668 _______________________________________________________