Re: Mersenne: Setu for Dual processor NT
On Sun, 18 Jul 1999, Brian J. Beesley wrote: > > Is there any way to set the affinity under NT automatically when a service > > starts up? > > Put "Affinity=n" into prime.ini (where n = 0, 1, 2, ...) This works > for both NTPrime and Prime95/NT. > > If this line isn't there, the processes are scheduled on the first > available processor at each timeslice. This costs about 5% on an idle > system and next to nothing on a system which is very busy (because > idle priority processes don't see much CPU), but it is expensive on a > system which has just a little load from other applications. > > I think "Affinity=n" may work with linux also. There's no support for explicit processor affinity in stock Linux, so I'd doubt that would work. On the other hand, the affinity of a process to stay at the same processor is very high, exactly to prevent that rescheduling performance hit seen in NT, so I wouldn't expect it to be a big problem. -- Henrik Olsen, Dawn Solutions I/S URL=http://www.iaeste.dk/~henrik/ Darth Vader: Luke, come to the dark side. Luke: No. Darth Vader: Your goodness has redeemed me. Die, emperor scum. Return of the Jedi, the Movie-A-Minute version _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Setu for Dual processor NT
> Is there any way to set the affinity under NT automatically when a service > starts up? Put "Affinity=n" into prime.ini (where n = 0, 1, 2, ...) This works for both NTPrime and Prime95/NT. If this line isn't there, the processes are scheduled on the first available processor at each timeslice. This costs about 5% on an idle system and next to nothing on a system which is very busy (because idle priority processes don't see much CPU), but it is expensive on a system which has just a little load from other applications. I think "Affinity=n" may work with linux also. Regards Brian Beesley _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Setu for Dual processor NT
If you use the affinity option under advanced it will set the CPU number into the ini file for that image. So if you have 2 CPU and two icons (one using the -A1 switch) then the exe image will use the proper affinity as found in the ini file for that icon. regards Michael.. Chip Lynch wrote: > > Use the -A switch (see the readme) to configure a separate image of the EXE. > > ALso set the affinity (under advanced) when it is running so the processor > > preference will be set in the control file (one image per processor). > > Is there any way to set the affinity under NT automatically when a service > starts up? Some of the machines I run this stuff on are multi-os, and I > very often switch between them, which means rebooting a lot. And I never > remember to set my affinities by hand againwhen I come back into NT. It > just kills performance in NT, tho, if you don't have the affinities set up > right. Doe UNIX variants have the same problem? I.E. Naieve timesharing > across CPUs with the huge resulting overhead? Just curious. > > ---Chip > >\\ ^ // > (o o) > ---oOO--(_)--OOo > | Chip Lynch| Computer Guru| > | [EMAIL PROTECTED] || > | (703) 465-4176 (w) | (202) 362-7978 (h) | > _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Setu for Dual processor NT
> Use the -A switch (see the readme) to configure a separate image of the EXE. > ALso set the affinity (under advanced) when it is running so the processor > preference will be set in the control file (one image per processor). Is there any way to set the affinity under NT automatically when a service starts up? Some of the machines I run this stuff on are multi-os, and I very often switch between them, which means rebooting a lot. And I never remember to set my affinities by hand againwhen I come back into NT. It just kills performance in NT, tho, if you don't have the affinities set up right. Doe UNIX variants have the same problem? I.E. Naieve timesharing across CPUs with the huge resulting overhead? Just curious. ---Chip \\ ^ // (o o) ---oOO--(_)--OOo | Chip Lynch| Computer Guru| | [EMAIL PROTECTED] || | (703) 465-4176 (w) | (202) 362-7978 (h) | _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Setu for Dual processor NT
Use the -A switch (see the readme) to configure a separate image of the EXE. ALso set the affinity (under advanced) when it is running so the processor preference will be set in the control file (one image per processor). Expect the speed to slow down per instance.. if I run one image it gets .22/LL if I run two images they get .25/LL if I run three images they get .33/LL if I run four images they get .4/LL go figure ... the overhead is a strange curve but at .4/ll with 4 working it takes about 28 days to complete or 7 days each avg. WHere with one at .22 it would be about 16 days for one LL. (if I run factors with the 4 processors they each complete a factor a day) 4 - 500mhz Xeon's w/2MB L2 and 1GB RAM Michael.. "Terry S. Arnold" wrote: > I am going to build a dual processor box running NT. How do I set things up > so I get copies of Prime 95 running on each processor. I want to get > maximum bang out of this combination. > > Terry > Terry S. Arnold 2975 B Street San Diego, CA 92102 USA > [EMAIL PROTECTED] (619) 235-8181 (voice) (619) 235-0016 (fax) > _ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: Setu for Dual processor NT
I am going to build a dual processor box running NT. How do I set things up so I get copies of Prime 95 running on each processor. I want to get maximum bang out of this combination. Terry Terry S. Arnold 2975 B Street San Diego, CA 92102 USA [EMAIL PROTECTED] (619) 235-8181 (voice) (619) 235-0016 (fax) _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
