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Cinzia

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Message 27996 - Posted: 29 Nov 2016, 7:47:22 UTC
Last modified: 29 Nov 2016, 7:49:25 UTC

The LHCb simulations application is now available on this project, if you would like to join us, you can choose to run LHCb tasks from the project preferences, this application requires Virtual Box.

The LHCb experiment wants to discover why after the Big Bang antimatter disappeared and what allowed matter to survive and build the Universe.
The objective of experiment is to record the decay of particles containing b and anti-b quarks, known as ‘B mesons’. The experiment’s detector is specifically designed to filter out these particles and the products of their decay.
Each one of LHCb’s sub-detectors specializes in measuring a different characteristic of the particles produced by colliding protons. Collectively, they gather information about the identity, trajectory, momentum and energy of each particle generated, and can single out individual particles from the billions that spray out from the collision point.

To know more about the experiment, you can visit the page:
http://lhcb-public.web.cern.ch/lhcb-public/
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Crystal Pellet
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Message 27997 - Posted: 29 Nov 2016, 9:12:54 UTC - in response to Message 27996.  

If Erik Verlinde's theory (Emergent Gravity and the Dark Universe) is right,
do you have to reconsider the LHCb experiment?
...and maybe other CERN experiments?

http://www.quantumuniverse.nl/emergent-gravity-and-dark-universe
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Message 27999 - Posted: 29 Nov 2016, 12:55:36 UTC - in response to Message 27997.  

It does make you wonder doesn't it CP?

That is what got me stuck over at the Einstein Project a few months after this one started......not that my thousands of hours will prove anything.
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Crystal Pellet
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Message 28000 - Posted: 29 Nov 2016, 17:23:08 UTC - in response to Message 27999.  

It does make you wonder doesn't it CP?

That is what got me stuck over at the Einstein Project a few months after this one started......not that my thousands of hours will prove anything.

thousands of hours - Oh, what's time, what's eternity?

I think Hamlet was wrong: the question should be "To be and not to be".
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Message 28003 - Posted: 29 Nov 2016, 22:38:17 UTC - in response to Message 28000.  

thousands of hours - Oh, what's time, what's eternity?

I think Hamlet was wrong: the question should be "To be and not to be".


Well time is a human thing.....and I suppose a redwood tree may have a tree clock hiding under the bark.

At first we think of all this time we have and then the day comes where you wonder how much is remaining.

I am at that remaining point and want that live forever shot that only goes to the ones that do something important with that time........since that trip to the Moon or Mars looks like a dream at this spacetime

Those butterflies and their theories......here it is hummingbird effect
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Message 28053 - Posted: 4 Dec 2016, 19:18:01 UTC

How is the priority selection of which tasks are sent to a host? My home computer has selected to accept tasks from all applications but it gets only tasks for LHCb. I have limited the concurrent LHCb tasks to 3 (memory reasons) but 5 cores are totally available for CPU crunching (3 cores is used by GPU tasks on other projects). So there would be room to run a couple of Theory tasks before my 16 GByte memory is full, but I don't get any.
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Message 28054 - Posted: 5 Dec 2016, 7:14:19 UTC

I'd be interested to know too, when you look at tasks in progress then the other apps are more in progress so seems like they are more common??
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Message 28212 - Posted: 22 Dec 2016, 17:18:46 UTC - in response to Message 28053.  
Last modified: 22 Dec 2016, 17:21:27 UTC

How is the priority selection of which tasks are sent to a host? My home computer has selected to accept tasks from all applications but it gets only tasks for LHCb...

I'm wondering this, as well. On my hexa-core 16GB RAM host, I allow CMS, Theory, SixTrack, and LHCb, but have yet to get an LHCb task. I run Atlas, as well, and have app_config files set to allow only 4 of the 2GB tasks to run at one time.
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Message 28224 - Posted: 23 Dec 2016, 13:30:49 UTC

I thought about this as I would balance the projects separately. I assume now the projects would be balanced by the LHC team.
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Message 28226 - Posted: 23 Dec 2016, 14:51:22 UTC

Is there a specification for the app_config.xml file for LHC@Home?

My machine has a quad core intel i5 cpu, but there is only 8GB of memory
available. I would like for LHC@Home to only run one instance at a time, but
my machine nearly died when the BOINC scheduler ran 4 LHC tasks at once! (Swapping its little disks in and out all over the place)

I thought I had an app_config file, but it seems to have gotten removed at some point in time recently.
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Message 28227 - Posted: 23 Dec 2016, 14:58:20 UTC - in response to Message 28212.  

How is the priority selection of which tasks are sent to a host? My home computer has selected to accept tasks from all applications but it gets only tasks for LHCb...

I'm wondering this, as well. On my hexa-core 16GB RAM host, I allow CMS, Theory, SixTrack, and LHCb, but have yet to get an LHCb task. I run Atlas, as well, and have app_config files set to allow only 4 of the 2GB tasks to run at one time.

Just guessing, but so it works with World Community Grid.

LHCb is a test application (in WCG-terms a Beta)
When requesting new work, first look whether 'running test applications' is enabled in your project preferences,
then whether there are workunits in the Beta-queue available (LHCb's mostly are). When not: random other applications from your preferences.

That would explain why you mostly get LHCb's.
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Message 28228 - Posted: 23 Dec 2016, 15:09:04 UTC - in response to Message 28226.  

Is there a specification for the app_config.xml file for LHC@Home?

Yes there is, but first try to control the number of tasks with your project preferences.

There you can set the Max # jobs
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Message 28229 - Posted: 23 Dec 2016, 15:13:11 UTC - in response to Message 28227.  

Crystal Pellet wrote:
LHCb is a test application.

Thanks, CP! I missed any mention of that and am getting LHCb tasks now that I have test applications enabled in my preferences.
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Message 28231 - Posted: 23 Dec 2016, 16:37:46 UTC - in response to Message 28226.  

You can adjust the settings in your account without need for app config now.
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Message 28290 - Posted: 29 Dec 2016, 21:51:15 UTC - in response to Message 28227.  
Last modified: 29 Dec 2016, 21:53:34 UTC

Crystal Pellet wrote:
When requesting new work, first look whether 'running test applications' is enabled in your project preferences,
then whether there are workunits in the Beta-queue available (LHCb's mostly are). When not: random other applications from your preferences.

So, CP, are you saying that test applications have highest priority? Is that why one of my hosts with the settings below has been getting only LHCb tasks the past several days?

Run test applications? [checked]
Run only the selected applications
SixTrack: yes
sixtracktest: yes
CMS Simulation: yes
LHCb Simulation: yes
Theory Simulation: no
ATLAS Simulation: no
ALICE Simulation: no
Benchmark Application: no
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Message 28291 - Posted: 29 Dec 2016, 22:32:26 UTC - in response to Message 28290.  

So, CP, are you saying that test applications have highest priority? Is that why one of my hosts with the settings below has been getting only LHCb tasks the past several days?

Run test applications? [checked]
Run only the selected applications
SixTrack: yes
sixtracktest: yes
CMS Simulation: yes
LHCb Simulation: yes
Theory Simulation: no
ATLAS Simulation: no
ALICE Simulation: no
Benchmark Application: no

It looks like you proved, what I was saying :lol:
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Message 28294 - Posted: 30 Dec 2016, 14:14:24 UTC - in response to Message 28291.  
Last modified: 30 Dec 2016, 14:15:04 UTC

It looks like you proved, what I was saying :lol:

Indeed! I just wanted to make sure I understood what you were saying. Interestingly, I just picked up a CMS task on this host. So, maybe he LHCb queue is running low.
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Message 28295 - Posted: 30 Dec 2016, 14:37:46 UTC - in response to Message 28294.  
Last modified: 30 Dec 2016, 14:39:36 UTC

It looks like you proved, what I was saying :lol:

Indeed! I just wanted to make sure I understood what you were saying. Interestingly, I just picked up a CMS task on this host. So, maybe he LHCb queue is running low.

The 3 queues for the VM-applications mostly have between 80 and 100 BOINC-tasks Unsent and are automatically refilled.
But when there are too many requests for 1 queue at the same time, the queue of the next application will be polled.
I've seen rather often that with only Theory selected and although there were Unsent tasks, I still got the message "No tasks are available for Theory Simulation".
After a 2nd or 3rd request I got a task then.
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Message 28296 - Posted: 30 Dec 2016, 16:18:55 UTC - in response to Message 28295.  
Last modified: 30 Dec 2016, 16:21:42 UTC

The 3 queues for the VM-applications mostly have between 80 and 100 BOINC-tasks Unsent and are automatically refilled.
But when there are too many requests for 1 queue at the same time, the queue of the next application will be polled.

I see, thank you.

So, as long as LHCb remains a "test app", I guess I'll have to change preferences periodically and load up on CMS tasks. Not ideal, but manageable.
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Message 28297 - Posted: 30 Dec 2016, 17:14:47 UTC

There was a discussion elsewhere about the balancing of project, so watch that space
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Message boards : LHCb Application : Info about the LHCb experiment


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