SETI@Home and Hyper-Threading

[Jonitus]

I've been crunching away at the WU's lately, and have come to the conclusion that HT hurts performance in SETI, more than it helps it. With two instances of SETI running, one for each logical processor, the times com in around 5 hrs average. With a single instance running, the WU's are completing at around 1:51 for the past 5 WU's. I've scoured around to try and determine what could cause for the lack of performance in HT. Maybe this will help some of you out there with HT rigs. I do better with one instance, letting all the physical processor chew, rather than two "logical processors".

 

[titanmiller]

One thing to remember is that alot of recently distributed WUs have varied in AR greatly. This seems like it could be possible as 2 WUs in 5 hours is about 2:30 per WU and a assuming that your past 5 WUs have been high AR WUs I dont see your times being too far off.

 

[Jonitus]

I should have quantified my statement better before posting. I am not getting 2 WU's per 5 hour period...it's 1 WU for 5 hours when running two instances.

If I could figure out how to set up SETIQue, maybe I would have more insight.

 

[titanmiller]

Originally posted by: Jonitus
I should have quantified my statement better before posting. I am not getting 2 WU's per 5 hour period...it's 1 WU for 5 hours when running two instances.

If I could figure out how to set up SETIQue, maybe I would have more insight.

Wouldnt that be correct? If it says it took 5 hours and the other WU that was running at the same time said it took 5 hours, that would mean that 2 were completed in 5 hours even though each individual WU took 5 hours? Sorry if I'm not understanding correctly.


Anybody else have an idea?



How many WUs does this system put out per day both with HT and w/o HT?

 

[BofRA]

Point you client to this proxy: reagancrw.homedns.org:5517. It is my SETIqueue so we can figure this out. I am very intertested in this since I have the stuff to buy some HT in my cart at newegg right now!!!

 

[Intelligence3]

I get 2 WUs every three hours (two instances running at the same time, each WU takes an average of 3 hours) running hyperthreaded. I get 1 WU every 2 hours when running only one instance. Running hyperthreaded means I get 16 WUs in a day, or 12 WUs running a single instance.

I'm not sure how you could only get 1 WU per 5 hours running 2 instances. If you are running two instances, it should be processing 2 WUs at a time. Both instances don't work on the same WU together at the same time.

 

[Jonitus]

Running hyperthreaded, with two instances running, I get about 7-9 WU's per day. Running a single instance, I am on my 13th for today. Wierd!!!

 

[Spacehead]

Jonitus ,
Your not running the GUI are you?

 

[BadThad]

Somethings not right on your system. I ran a customer system for 10 days: 2.4C@3.01GHz, Abit IC7, HT enabled, Corsair XMS3500 CAS2 5:4@ ~400 MHz DDR. Using SETI Driver and 2 processes, I averaged 16-18 wu's/day. With only a single process I was getting ~11-12 wu's/day. HT is DEFINATELY the way to go.

My results are typical of everyone elses I've read about...except for you....somethings not right with your setup.

 

[HayHauler]

I just knew you couldn't resist....
hehehe

:beer::beer::beer:

 

[Jonitus]

Originally posted by: badthad
Somethings not right on your system. I ran a customer system for 10 days: 2.4C@3.01GHz, Abit IC7, HT enabled, Corsair XMS3500 CAS2 5:4@ ~400 MHz DDR. Using SETI Driver and 2 processes, I averaged 16-18 wu's/day. With only a single process I was getting ~11-12 wu's/day. HT is DEFINATELY the way to go.

My results are typical of everyone elses I've read about...except for you....somethings not right with your setup.

So be a good fellow and help me figure it out. Tell me how you had everything configured, what settings you used, etc. I would like to figure it out.

 

[Jonitus]

Here are my settings:

2 separate directories for SETI, SETI_1 and SETI_2

shortcuts for each respective SETI driver in the startup folder

SETI driver settings are as follows:

hide processing = yes
auto transmit = yes
set processor affinity = yes
desired cache = 40
SETI client priority = low
Use SETI driver = yes
Create SETILog.csv = yes

I have gone into my BIOS and verified my RAM timings, as well as my actually running HyperThreading on the processor and Dual-channel for the memory.

Looking at the Task Manager, the CPU usage is 50% on CPU0. I can manually assign processor affinity to each separate instance of SETI to each logocal processor, but the settings revert automatically after 30 seconds. I can set the priority of each process to normal, and the CPU usage will climb, but that setting too, will revert after 30 seconds. No matter what I try, the CPU usage never stays above 50% on CPU0, with CPU1 staying idle.

SETI Driver is reporting estimated completion times of around 2 hours, so logically, I should be chewing through close to 20 plus WU's a day. I am, however, barely getting 10 most days.

What is causing this?

 

[BadThad]

OK, first off, do NOT run 2 copies of SETI driver. Simply copy the exe's for seti driver and the seti CLI into a single directory. Execute seti driver. It should automatically insert a "2" into the "Maximum Processes" section. Everytime I've run Driver on a dual CPU system or an HT system, it has automatically detected "2" cpu's. Don't check the "Set Processor Affinity" box, it doesn't seem to do anything anyway. Enter the "desired cache size" then.....

Check the "Use SETI Driver", "Create SETIlog.csv", "Hide Processing", "Low Priority"....then hit "transmit". When the CLI comes up, enter ur seti email address let it rip. Then, check off "autotransmitt" and hit the "save config" button.

If Driver doesn't auto detect 2 CPU's, enter a "2" in maximum processes. However, I repeat, it should have detected the HT system as dual CPU. Check CPU utilization after Driver has the cache full, you should see 2 CPU's in task manager with each at 100%. I think your problem was running two instances of seti driver. Tell me you see 2 CPU's in Task Manager>Performance!

 

[Jonitus]

Follow the link...is this what it should look like?

link

 

[BofRA]

That is exactly what it should look like!!!

Now lets get some results!!!

 

[MrBadidea]

So what should I be doing with my dual xeon 2.4s w/ HT?

Run 4 instances?

Going to have a play around and see what makes the biggest difference - FreeBSD w/ HT & w/o HT and Gentoo w/ HT & w/o HT

 

[lobadobadingdong]

Originally posted by: MrBadidea
So what should I be doing with my dual xeon 2.4s w/ HT?

Run 4 instances?

Going to have a play around and see what makes the biggest difference - FreeBSD w/ HT & w/o HT and Gentoo w/ HT & w/o HT

4 instances with that...mmmm might speed things up, but the memory bandwidth sucks on xeons(when running 2 or more), so you'll have to try it out to be sure, do it and let us know

 

[BadThad]

Originally posted by: Jonitus
Follow the link...is this what it should look like?

link

Absolutely! That's perfect man.

 

[BadThad]

Originally posted by: MrBadidea
So what should I be doing with my dual xeon 2.4s w/ HT?

Run 4 instances?

Going to have a play around and see what makes the biggest difference - FreeBSD w/ HT & w/o HT and Gentoo w/ HT & w/o HT

Most definately.....don't worry about bandwidth, run 4 processes and watch that beast crank out the wu's!

 

[Smoke]

 

[JWMiddleton]

Have we gotten any results from the revised setup??

/me wants one! :evil:

 

[Jonitus]

The evised setup appears to be working well, but leaves me with a question:

When SETIDriver makes an entry in the .csv file, is it done at the completion of each and every work unit? From viewing the file, entries are time-stamped approximately 3 hours apart. SETIDriver routinely reports three-hour completion times. Does this mean that I am completing 2 WU's every three hours, but getting only one log enrty for those 2 WU's?

Checking Smokeball's site, it seems I am well on my way to completing more WU's today than I have been (hard to tell though, since he's GMT, and I am 6 hours behind that)

 

[BadThad]

Originally posted by: Jonitus
The evised setup appears to be working well, but leaves me with a question:

When SETIDriver makes an entry in the .csv file, is it done at the completion of each and every work unit? From viewing the file, entries are time-stamped approximately 3 hours apart. SETIDriver routinely reports three-hour completion times. Does this mean that I am completing 2 WU's every three hours, but getting only one log enrty for those 2 WU's?

Checking Smokeball's site, it seems I am well on my way to completing more WU's today than I have been (hard to tell though, since he's GMT, and I am 6 hours behind that)

It's appended after the wu has been returned to S@H. Just wait 24 hours and then check. You should see that the system has completed ~17 wu's in 24 hours.....w00t!!!! I'm on my way to building one.....very soon.

 

[Wiz]

I remember that when I was running seti on a duallie checking the "set processor affinity" helped produce more WU's per day.
Is it the same with a HT P4?

 

[Smoke]

Originally posted by: Jonitus


Checking Smokeball's site, it seems I am well on my way to completing more WU's today than I have been (hard to tell though, since he's GMT, and I am 6 hours behind that)

Hey WIZ, you just can't get any respect ... can you?

Stats brought to you by "WIZ" & "The_TeAm"

lol