"On multiprocessors, at most use: x processors" option is ignored

[LAZA]

On the WCG site, the rules are avowed so:
"If you are using version 6.2 of the software, then the number of processors used will be the lesser of the two fields below. If you are using a version before 6.2, then only the 'at most' field will be used."

I wanted to change my settings from 3 to 2 CPUs, cause of the great heat outside (and inside).
But this option is ignored by boinc (i can see the 2 CPUs set on all other BOINC projects too!).
If i set it to 4 or 3 CPUs it works as expected, - but 1 and 2 is not only ignored, i get an message after reloading the profile:

Di 18 Jun 2013 17:25:27 CEST | | max CPUs used: 3

In Leiden Classics and eOn2 i can see the right number:
On multiprocessors, use at most 1 processors
Bei mehreren Prozessoren, nutze höchstens 1 Prozessoren

I tested this with the original Ubuntu version 7.0.27, 7.0.65 (backports) and the test version from Costa Franco (Locust of Borg) 7.1.10 with the same result.

.

Xubuntu 12.04.2

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: boinc (not installed)
ProcVersionSignature: Ubuntu 3.5.0-34.55~precise1-generic 3.5.7.13
Uname: Linux 3.5.0-34-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu17.3
Architecture: amd64
Date: Tue Jun 18 17:17:38 2013
InstallationMedia: Xubuntu 12.04.2 LTS "Precise Pangolin" - Release amd64 (20130214)
MarkForUpload: True
ProcEnviron:
 LANGUAGE=de_DE:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: boinc
UpgradeStatus: No upgrade log present (probably fresh install)

[Gianfranco Costamagna (costamagnagianfranco)]

Freely quoting from boinc_alpha list
SekeRob
Seen several times on the WCG member forums there was the assertion that
the particular rule after 6.2.28 is to 'only' use the & of processors. I
did test percent of processors on my Octo, in Windows 7-64, and 87.5 did
drop the running threads to 7,

18/06/2013 19:29:57 | | Number of usable CPUs has changed from 8 to 7.
18/06/2013 19:29:57 | | max CPUs used: 7
18/06/2013 19:29:57 | | don't use GPU while active
18/06/2013 19:29:57 | | suspend work if non-BOINC CPU load exceeds 75 %
18/06/2013 19:29:57 | | (to change preferences, visit a project web
site or select Preferences in the Manager)
18/06/2013 19:29:58 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-45_0000011_0446_4 (left in memory)

  even 25% dropped it to just 2.

18/06/2013 19:31:04 | | Number of usable CPUs has changed from 7 to 2.
18/06/2013 19:31:04 | | max CPUs used: 2
18/06/2013 19:31:04 | | don't use GPU while active
18/06/2013 19:31:04 | | suspend work if non-BOINC CPU load exceeds 75 %
18/06/2013 19:31:04 | | (to change preferences, visit a project web
site or select Preferences in the Manager)
18/06/2013 19:31:04 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-35_0000018_0355_0 (left in memory)
18/06/2013 19:31:04 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-35_0000017_0097_0 (left in memory)
18/06/2013 19:31:04 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-35_0000017_0044_0 (left in memory)
18/06/2013 19:31:04 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-35_0000018_0741_0 (left in memory)
18/06/2013 19:31:04 | World Community Grid | [cpu_sched] Preempting
DSFL_00090-35_0000018_0555_0 (left in memory)

Alternating here due the coming and going heat. Since presently testing
the WCG build 7.0.68 [the DCF fix applied, as properties no longer shows
it on this project, but on others without the <dont_use_dcf/> do in the
BM], tried it just now, with the said 25% in local prefs and 2
processors on website, leaving the % there at 100%. Updated, and then
increased local pref to 37.5%.

18/06/2013 19:32:42 | | max CPUs used: 2
18/06/2013 19:32:42 | | don't use GPU while active
18/06/2013 19:32:42 | | suspend work if non-BOINC CPU load exceeds 75 %
18/06/2013 19:32:42 | | (to change preferences, visit a project web
site or select Preferences in the Manager)
18/06/2013 19:32:42 | World Community Grid | [sched_op] Deferring
communication for 21 sec
18/06/2013 19:32:42 | World Community Grid | [sched_op] Reason:
requested by project
18/06/2013 19:33:24 | World Community Grid | General prefs: from World
Community Grid (last modified 18-Jun-2013 19:32:29)
18/06/2013 19:33:24 | World Community Grid | Host location: none
18/06/2013 19:33:24 | World Community Grid | General prefs: using your
defaults
18/06/2013 19:33:24 | | Reading preferences override file
18/06/2013 19:33:24 | | Preferences:
18/06/2013 19:33:24 | | max memory usage when active: 6918.88MB
18/06/2013 19:33:24 | | max memory usage when idle: 7732.87MB
18/06/2013 19:33:24 | | max disk usage: 5.00GB
18/06/2013 19:33:24 | | Number of usable CPUs has changed from 2 to 3.
18/06/2013 19:33:24 | | max CPU...

[Gianfranco Costamagna (costamagnagianfranco)]

quoting David Anderson

If the "% of processors" is specified (i.e. nonzero)
then the "use at most N" is ignored.

We want to discourage the use of "use at most N" because it's
not future-proof.

-- David

[LAZA (laza74)]

Thanks costamagnagianfranco for the infos!

I was irritated about that... cause for _me_ (straight logic!?!) for example *tested* so (AMD 4-core):

1.
max. # CPUs: 3
use 99 %
--> cpu load overall: 74,25 % (that was my year long approved setting and work so very good!)

2.
max. # CPUs: 2
use 50 %
--> cpu load overall: 50 % (not as i expected!), should be 25%

3. tested
max. # CPUs: 4
use 10 %
--> cpu load overall: 10 % (as expected)

4. tested
max. # CPUs: 2
use 100 %
--> cpu load overall: 50 % (decide yourself, what you expected)

I see here some possibilities to make things clear:
A.) Change the description on the project sites, and please add some more information cause it is vital for the machine.

B.) Delete the option "On multiprocessors, at most use: processors" in "Advanced Options" on the websites and just work with the percent number.

C.) Leave all the applications as they are and fix the bug.

Or did i miss here something or missunderstood sekerob testings...?

[LAZA (laza74)]

Sorry forgot the worst case:

5.
max. # CPUs: 2
use 75 %
--> cpu load overall: 75 %, should (for me) be only 37,5%

[Gianfranco Costamagna (costamagnagianfranco)]

Please try this ppa and boinc 7.8.1, and let me know if the problem still occurs by setting back the status to "new"
https://launchpad.net/~costamagnagianfranco/+archive/ubuntu/boinc/

[Launchpad Janitor (janitor)]

[Expired for boinc (Ubuntu) because there has been no activity for 60 days.]