I have been running SETI@home (and later also rosetta) on my Linux desktop with a 6-core AMD since September. BOINC automatically determined it could run 6 tasks in parallel and has been doing that ever since.

Now I've just added another linux box, also with a 6-core AMD, but this time BOINC would only run one task. I wondered why and looked into the Computing Preferences on the web. I noticed "On multiprocessors, use at most 1 processors" which was puzzling. I changed that to 6. But then when I do "Computing Preferences -> Clear" in BOINC on the old desktop, it says in the Event Log "Number of usable CPUs has been changed from 6 to 1" and all of a sudden, that too only runs one task! :-(

What's going on here? How can I make it understand it has 6 cores available???

Old box: Linux Mint 14, BOINC Manager 7.2.33
New box: Linux Mint 17, BOINC Manager 7.2.42

Old box: http://setiathome.berkeley.edu/show_host_detail.php?hostid=7105433
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Bjorn in Norway

At a guess, it sounds as though your global preferences (configured on the SETI@home site) has been set to use no more than 1 CPU. You can change this at Account -> Preferences -> Computing Preferences -> On multiprocessors, use at most... [x processors]

Assuming I'm understanding your situation correctly, of course.

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Soli Deo Gloria

But it *was* set to 1 even before this. And when I tried manually setting it to 6, BOINC wouldn't take it but reduced it to 1 anyway.

Update: I now tried setting it to 0, it had no effect. BOINC still thinks I have only one CPU.

All right, I misread your initial post to be about the settings from BOINC. CPU usage count should be big enough to cover the number of CPU cores, in your case 6. You say you've done this. I assume CPU usage percentage and time have also been set to 100%. Beyond that, I can't advise any more beyond seeing what's actually in your account and BOINC preferences.

This is why I usually keep quiet, I don't like getting things wrong or being seen as unhelpful.

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Soli Deo Gloria

It's also worth noting that the new computer was correctly registered as having 6 CPUs (cores) but then BOINC overrules that and decides it has only 1. The same happens when I run a CPU benchmark: I can observe it only runs it on a single core.

Ah well, one good thing about this is that the old computer is much quieter now that the fan has slowed down....

On multiprocessors, use at most
Enforced by version 6.1+ 100% of the processors

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Avians and Myrmicats, the Octospiders, and the Humans all living in one huge cylinder in space called RAMA.

I just discovered: this was set to 0.00% in the local preferences in each BOINC. I changed that to 100% and now it runs 6 tasks on both computers! :-) But I think this is broken, it should do this by default. Somehow it didn't help to set it to 100% on the web.

Ether way you got them working properly, and I would like to think that I helped a little to see what was going wrong.:-)

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Avians and Myrmicats, the Octospiders, and the Humans all living in one huge cylinder in space called RAMA.

Thanks but I had actually solved it myself before I saw your reply. :-)

I just discovered: this was set to 0.00% in the local preferences in each BOINC. I changed that to 100% and now it runs 6 tasks on both computers! :-) But I think this is broken, it should do this by default. Somehow it didn't help to set it to 100% on the web.

Local preferences over-ride the web-page preferences.
There are some things that can only be set on the account page, but those things that can be set in both the account page and the individual computer, the indiviudual computer preferences control.

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Donald
Infernal Optimist / Submariner, retired

But is says "Click Clear to restore web-based settings" and that's what I did. Also, it says that a setting 0 for this parameter would be ignored but apparently it wasn't.

It's also strange that a fresh install of BOINC on the new box would create a config that by default does not utilize the CPU cores I have.

But never mind, it works now. :-)

But is says "Click Clear to restore web-based settings" and that's what I did. Also, it says that a setting 0 for this parameter would be ignored but apparently it wasn't.

It's also strange that a fresh install of BOINC on the new box would create a config that by default does not utilize the CPU cores I have.

But never mind, it works now. :-)

It wouldn't be the first time that what you expect to happen doesn't match what really happens. Sometimes it's a feature change, sometimes it's a bug.

Care to go through it all again, noting exactly what you wrote (or what BOINC wrote) in which box? See if you can reproduce it? I think there's a rolling pin I can borrow to get the message through.

As it's supposed to work, barring any bugs and errors possible in the various codes:

The value of On multiprocessors, use at most N processors is the absolute minimum amount of CPUs that BOINC can use. This value can be set to zero, which then also means zero (use none, not use all). Default value is use all of the available processors. Minimum can be zero but only when "% of processors" is non-zero else defaults back to 1, maximum is 9999.

The value of On multiprocessors, use at most X% of the processors is the fine tuning method with which you can set the amount of CPUs BOINC. Default set to 100%, can be set to 0%.
It is not used to fine tune the value of "use at most N", which many people seem to think.

For the website preferences, since both these values can only be set through there: when the "% of processors" is specified (i.e. nonzero), then the "use at most N" value is ignored.
Only when "% of processors" set through the web-preferences is zero, fall back to the value specified in "use at most N". Since the use of "use at most N" is not deemed future-proof, its use is being discouraged.

For the BOINC Manager local preferences: these preferences will only override those preferences that can both be set through here and through the web-preferences.
Any of the other preferences will be read from the appropriate file, but can not be changed through local means.

Only on the local preferences will the "0 means no restriction for this setting" value on the "use at most X% of the processors" preference reset the value to default use, which is 100%.
Exemplified by my computer showing it as, when going from 50% to 0%:

09/06/2014 08:56:24 |  | max CPUs used: 2
09/06/2014 09:17:05 |  | Number of usable CPUs has changed from 2 to 4.

Have fun debugging that. I always get lost halfway through. :-)

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yes I found mine was also reset to one on the website.

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Mike Bader
BOINC V7.16.5
http://setiathome.berkeley.edu/team_join_form.php?id=5 - Join Our International Team
[img]http://boinc.mundayweb.com/one/stats.php?

Other team members reporting the same thing.
Not sure when, I just noticed mine this AM when adding another computer to my SETI farm. SETI server glitched at some point.

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Mike Bader
BOINC V7.16.5
http://setiathome.berkeley.edu/team_join_form.php?id=5 - Join Our International Team
[img]http://boinc.mundayweb.com/one/stats.php?