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Doctor Q
Sep 27, 2002, 09:03 PM
I've been doing benchmark tests on my new Dual 1.25GHz Power Mac G4.

Here are my SETI@home results.

The notation xx:yy:zz means xx hours, yy minutes, zz seconds. I averaged times from multiple work units to get more accurate results. One work unit took an hour less than all the others (sometimes SETI determines that a work unit is useless and aborts its computations early), so I omitted that run from the results.

1. The minimum "Average CPU time per work unit" was achieved running the CLI (command line interface) version of SETI, with the energy saver features turned off and no other processes running.

CPU time: 5:40:48 (baseline)
Elapsed time: 5:40:50 (baseline)
CPU utilization: 100% (baseline, meaning one processor fully occupied)

Explanation: This is the fastest that this Mac can run. Nothing but Mac OS X 10.2, the Terminal application, and SETI were running. Only one CPU was used. Mac OS overhead is extremely minimal (a few seconds in over 5 hours).

2. CLI version, energy saver on:

CPU time: 5:48:09 (2.2% over baseline)
Elapsed time: 5:49:30 (2.5% over baseline)
CPU utilization: 98%

Explanation: A little more Mac OS overhead, but essentially the same.

3. Screensaver (graphical) version, energy saver on, graphics display timeout after 30 minutes:

CPU time: 5:52:11 (3.3% over baseline)
Elapsed time: not measured
CPU utilization: 97%

Explanation: This is a typical way you might use SETI@home. The graphical display (for 30 minutes) adds a little overhead, but not much, since one CPU can handle the graphics while the other is still number crunching the work unit.

4. CLI version, energy saver off, with 2 copies of SETI@home running at once:

CPU time: 11:47:57 total
5:53:59 per unit (3.9% over baseline)
Elapsed time: 5:56:55 total (4.7% over 1 unit baseline, but for 2 units!)
2:58:28 per unit
CPU utilization: 191%

Explanation: I got twice the amount of number crunching done (2 units completed) in only a few minutes more elapsed time than when I did 1 unit. The second CPU is in almost constant use. Good for you, Dual Mac!

5. CLI version, energy saver off, with 3 copies of SETI@home running at once:

CPU time: 17:45:20 total
5:55:07 per unit (4.2% over baseline)
Elapsed time: 8:56:37 total (57% over 1 unit baseline, but for 3 units)
2:58:52 per unit
CPU utilization: 191%

Explanation: You can run 3 (or more) units at essentially the same rate as 2 units, i.e., nnn units will take nnn/2 as much elapsed time as 2 units. Both CPUs will be almost fully occupied. Process switching adds neglible overhead.

Bottom line:

* To benefit from dual CPUs, run 2 or more SETI@home processes at the same time in CLI mode.

* Energy saver settings have minimal effect.

* With one SETI@home processing running, it is OK to leave the graphics display on. But you might as well set it to time out if you won't be watching it.

* Having dual processors lets you complete units at twice the elapsed time rate of a single processor of the same speed by running two or more SETI processes at once. In this case, set the screen to go dark (no graphics) if you use the screensaver version, since both CPUs will already be occupied.

* The measure of "Average CPU time per work unit" (as shown on the SETI summary pages) will be slightly less when running multiple processes at once. The results when you run dual processes on dual processors will appear the same as if you run two separate single-processor computers that have the same CPU speed.

And that's enough benchmarking for one week!



Falleron
Sep 28, 2002, 09:52 AM
Less than 6 hours is quite good. My original dual 1ghz (non DDRAM) can manage to do them in about 6 and a half hours (2 units).

Bob Dobbs
Oct 18, 2002, 05:00 PM
just got a new dual 1 gig -my times while doing lots of other stuff (final cut, photoshop, web and so on) is around 8 or 9 hours. but 2 at once when i go home sounds very cool.

how?

Falleron
Oct 18, 2002, 05:13 PM
You need to be running OSX. Once in OSX, all you need to do is install SETI twice (into sepearate directories). You have to use the CLI version (not the screensaver version). Below is the link to the CLI version.

ftp://ftp.cdrom.com/pub/setiathome/setiathome-3.03.powerpc-apple-darwin1.2.tar

Eg. SETI1 + SETI2. Then fire up the clients manually or use a program such as SETICNTL to manage the clients (no need to mess around with the command line). You can get SETICNTL from :

http://www.versiontracker.com/macosx/

Just do a search and you will find it.

Bob Dobbs
Oct 18, 2002, 05:23 PM
how do i install on a sep directory?

i use a mac to do print graphics for a living (and video editing on the side) - they pay peopel to fix it when there is a prob. -

i got the 2nd version of seti, but dont know where to install it. is a directory another disc? lol probably wrong.

Doctor Q
Oct 18, 2002, 05:33 PM
When you install the Command Line Interface (CLI) version, you pick a folder (directory) to install it in, e.g., /Applications/seti1.

In a Terminal window, you can then make a second copy of the application using the commands to copy a directory:

cd /Applications
cp -r seti1 seti2

To start one running in a Terminal window, you can type

cd /Applications/seti1
./setiathome

To start a second copy running at the same time, open a new (i.e., second) window in the Terminal application and in it type

cd /Applications/seti2
./setiathome

You can stop either one at any time by pressing Control-C while that Terminal window is the active window.

The very first time you run setiathome, it interviews you about your user name and any team you want to join. I recommend the MacRumors team!

finchna
Oct 18, 2002, 05:38 PM
Originally posted by Doctor Q
I've been doing benchmark tests on my new Dual 1.25GHz Power Mac G4.


1. The minimum "Average CPU time per work unit" was achieved running the CLI (command line interface) version of SETI, with the energy saver features turned off and no other processes running.

CPU time: 5:40:48 (baseline)
Elapsed time: 5:40:50 (baseline)
CPU utilization: 100% (baseline, meaning one processor fully occupied)

Explanation: This is the fastest that this Mac can run. Nothing but Mac OS X 10.2, the Terminal application, and SETI were running. Only one CPU was used. Mac OS overhead is extremely minimal (a few seconds in over 5 hours).

2. CLI version, energy saver on:

CPU time: 5:48:09 (2.2% over baseline)
Elapsed time: 5:49:30 (2.5% over baseline)
CPU utilization: 98%


This is interesting. I'm running one instance of the graphical interface and one of the command line and I find the graphical quite a bit faster (based on percentage completion--I've not checked the time passed. Do you check elapsed time in SetiContol or via the terminal? If terminal, how do you get it?). I do have the nice setting of the CLI version on 20--the nicest level. What's level is yours at? Ciao,

Nathan

Doctor Q
Oct 18, 2002, 10:57 PM
I tried nice 20 but I can't really tell the difference, so I run them at the default of nice 0, even when I'm working on other things.

I have a theory that the graphical version runs as quickly as the CLI version because the video card (a third processor in your dual processor machine!) is handling the graphics.

How to get stats

In a Terminal window (other than the one running setiathome, you can check the progress in the current work unit as follows:

cd /Applications/seti1 (or wherever)
grep prog state.sah

The output will be something like this:

prog=0.14159265

which means it is 14.159265% of the way done with that work unit.

You can check the number of cpu seconds used so far on the current work unit with

grep cpu state.sah

You can check the total cpu seconds used for all previous work units submitted to Berkeley with

grep cpu user_info.sah

I wrote myself a shell script to do these commands, so I can find out where I stand anytime I have a sudden need to know.

Finally, you can check when a command (setiathome in this case) started (to compute elapsed time) with the ps -u command.

chmorley
Oct 19, 2002, 12:11 AM
After running the CLI version for a while, I tried SETI Menu (http://www.versiontracker.com/moreinfo.fcgi?id=15979&db=mac). While it took a little tweaking, I like it. It takes almost no cycles and it gives me current statistics. Not a huge advantage over opening a terminal window, but a small one, nonethless (IMHO).

I'm interested if others have tried it.

Chris

Falleron
Oct 19, 2002, 04:13 AM
I like SETICNTL because it allows me to have as many units stored on my computer as I want. As I only connect using a modem, this is a useful feature for me.