Re: AW: NONMEM runtimes

From: Jos Javier Zarate Subject: Re: AW: [NMusers] NONMEM runtimes Date: Mon, 29 Apr 2002 23:17:54 +0200 Dear all I think that it is possible that you haven't activated your 32 bit access in your Linux installation (if I recall correctly some Linux distributions don't activate it by default) also try to check if you have DMA activated (it also improves disk performance) SSE and SSE2 are SIMD instruction sets that are only related to FPU work and the improvements described in the initial message of this thread appear to be related mainly to INT performance. Anyway Intel compilers increase performance of most applications (even for AMD processors if you don't apply specific P-4 optimizations) I tried the SIMD options on DEC Alpha microprocessors with Compa (DEC) compilers with not too much success. When changing some parameters I managed to improve performance by reducing disk usage. Take into account that Linux appears not to be too P-4 friendly (don't know the reasons) I think that this is a problem related to Linux behaviour and not compiler choice. I suspect that NONMEM would need to be substantially rewritten in order to get the benefits of using modern compilers and CPUs. Intel compilers haven't been listedas reccomended compilers for NONMEM. Other programs tested with V5.xx (e.g. POVRAY) caused erroneus results when some optimizations were applied: You should be careful with your results if you apply aggressive optimizations. Good luck JJ Zarate Departamento de Compras Clnica Universitaria de Navarra http://www.unav.es/cun/ *******