[cwasko]

Right now I'm partly running SETI on 2 MacOS X Servers. I'm sure that the command line app will run on MacOS X PB (I hope). So... my question is... Will seti on a MacOS X PB on a Dual CPU G4 run 'twice' as fast (I know that seti is not, and probably will not be optimized for G4)? Becasue, theoretically, apps for MacOS X PB do *not* need to be programmed for the multiple cpu thang...

I'm just dying for a reason to buy a dual...

[iPad]

It won't run twice as fast, SETI@Home will run under classic if you use OS X PB, and also SETI@Home is not optimized for multiprocessors.

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People aren't as dumb as you think. Wait, what was I thinking, 90% of the world uses WINDOWS!
You don't like Macs? Good, more for me.

[cwasko]

Originally posted by iPad:
It won't run twice as fast, SETI@Home will run under classic if you use OS X PB, and also SETI@Home is not optimized for multiprocessors.

Uhhh... I can assure you that the copy of SETI that I'm running on my MacOS X Server will *not* run in classic. Goto the SETI Download page and look for the UNIX versions (http://setiathome.berkeley.edu/unix.html). If you scroll down, you will eventually see a version "powerpc-apple-rhapsody5.6:". This is a MacOS X Server *native* version.

I would also assume that this version will run on MacOS X Public Beta. Now... since developers do not have to program specifically to take advantage of multiple CPU's on MacOS X Public Beta; I was curious as to wether this would also apply to a UNIX prompt, OS X *native* version of the SETI client.

If the theory does apply, then yes, SETI *will* run almost twice as fast on a multiple CPU computer running MacOS X Public Beta.

[OoklaTheMok]

The rhapsody client is not multithreaded. You'll have to run two instances. Use the -cpu x parameter to set which cpu which runs on.

Please sumit a benchmark to www.teamlambchop.com using the standard benchmark file. That's what I'll be doing but I only have an iMac/500. I'm going to bench in OS X and Darwin with the rhapsody 5.6 client (if possible) and compare with the mac 2.04 time on the same machine in OS 9 and Classic. If you could do the same on your machine and add in OS X Server as well to the mix that would give a good benchmark to be there among the mostly-PC results on the page there now.

[brock76]

If you have a Dual processor, then i suggest along the lines that OoklaTheMok is suggesting. You can run two seti clients at the same time by using the -cpu x command. Just desinate one client to processor 1 and the other to processor 2. Make sure you use a CLI version of Seti and not the classic OS version to do this.

I have a dual at work but I'm not going to throw MacOS X on it quite yet. Some reports of the firewire drivers conflicts were enough for me to wait on the GM version of X.

But I know this is possible in a BSD kernel to desinate processor usage.

[OoklaTheMok]

Actually, I think it will work just fine even if you don't use the -cpu switch as long as you run both clients from different folders. OS X will distribute the threads among processors all by itself. And you can't run them from the same folder anyway.

Personally, I would love to run it on a dual G4, but I don't have one.

Also, I have found that the crontab solution named in the readme seems only to work if you log in as root and then log back in as your normal user. Following the instructions in the readme, seti is now running in the background for me and I can never tell. Nothing is slowed down at all. The joys of PMT!

This may not be very helpful, but you might find it interesting.

Let me introduce myself, I am Godcopp from the OCN seti team and I run an Abit BP6 dual Celeron motherboard running dual 466 Celerons overclocked to 602.

This may not apply to the new dual Mac, which is a beautiful machine BTW, but I run two instances on Seti on my machine. Just one instance of Seti will not run twice as fast as a similarly equiped single processor system. The benefit of dual CPUs comes in being able to run two of the programs.

For example, a single 466 celeron @ 602 might do a WU in 8 hrs. But if I run two instances of Seti with dual CPU's I'll complete two WUs in about 11 hrs. Giving an average time of 5.5 hrs per WU. Even tho the WUs will have taken 11 hrs to complete, you would have completed 2 in that time.

I assume the same basic principals will apply to the Dualie Mac, when such a thing becomes capable. I hope this information has been helpful and good luck in your crunching.

Godcopp out.

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Skunk Workx Technologies Inc.

Stealth computers for the 21st century and beyond.

[Bockie]

Godcopp, Thanks for the benchmarks on your times! Has anyone running a G4 MP have similar times to compare?

[SkiBikeSki]

Applications do need to be optimized for the MP thang. Read Macworld's article on the MP Power Mac in their November issue. They say that OSX can put two single processor apps on different processors, but each with only have one processor. You still need to write an app for MP, but it is not as hard as before since now we have cocoa.

Also will you be able to run two copies of SETI simultaneously. Won't it run in the classic environment, and won't both copies look to the same place for the WU. It'd be great if we had someone with an MP who tried these ideas out.

[cwasko]

SkiBikeSki,

Read the first 4 posts to this thread. These answer your questions.

[Joe Cool]

I have a dual G4 450 and Public Beta. I run two coppies of seti all the time. I do about 2 every 6 1/2hrs. It is not quite as fast per unit, but it still beats any thing out there. I haven't tried asgining which processor each copy uses, but I will se if it makes a difference.
Does anyone have any other speed tips?

[TNproud2b]

Joe Cool, just for comparison - it takes my dual Pentium3's @ 900MHz 5.5 hours to complete 2 work units, as well...

I know folks with Dual Xeons that complete 2 work units in 30min....well..extemely overclocked Xeons, that is.

[This message has been edited by TNproud2b (edited 10-13-2000).]

[Elderloc]

We have quad Xeon's at my work and just for giggle one time i put seti on it. Funny things that it didn't run very fast the server was a quad xeon 550 with 1 gig of memory.

Maybe it's just because it was an ibm.