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Moving multicore out of beta on Mon 29th August

Atlas news - Fri, 08/26/2016 - 13:27
We intend to move the multicore app out of beta on Monday the 29th August. This means that by default everyone will get both singlecore and multicore WU.

The main motivations for this are that multicore provides better CPU and memory efficiency, and we only have to manage a single stream of tasks instead of two.

If you do not want to run multicore you can disable it in your ATLAS@Home preferences in the option "Run only the selected applications"

By default the tasks will use as many cores as you have allocated to BOINC. For tuning the number of cores that the tasks will use you can create an app_config.xml file as described in this thread

At some point we plan to discontinue the singlecore app and run only multicore. The multicore app will also run on 1 core so you can still continue with ATLAS even with a single core.

Happy crunching!
The ATLAS@Home team
Categories: Atlas news

Multi-core version 1.04 with support for VirtualBox 5.1, OS X and graphics

Atlas news - Tue, 08/23/2016 - 13:27
Version 1.04 of the multicore app has been released with the following improvements:

- support for VirtualBox 5.1
- support for OS X (finally!)
- graphics (same as single core app)

Thank you for your continued support of ATLAS!
Categories: Atlas news

3 TRILLION EVENTS REACHED BY TEST4THEORY TODAY !!!

vLHCathome news - Sun, 08/21/2016 - 10:23
Congratulations and thanks to all our volunteers for helping CERN to reach the extremely impressive total of 3 Trillion events successfully simulated on our Theory project.

Further announcements and testimonials from our scientists will be posted later!
Categories: vLHCathome news

Please don't upgrade to Virtual Box 5.1.2

vLHCathome news - Mon, 08/08/2016 - 15:22
Please don't upgrade to Virtual Box 5.1.2 as it does not seem to work for us at the moment. An issue(#1606) has been submitted to the developers.
Categories: vLHCathome news

Version 2.01 with VirtualBox 5.1 support

Atlas news - Thu, 08/04/2016 - 13:46
We have released v2.01 of ATLAS@Home (single-core) with updated vboxwrappers to support VirtualBox 5.1. This should help with the large number of STATUS_ACCESS_VIOLATION errors that happen with v2.00. Please let us know if you still have problems running with VirtualBox 5.1.
Categories: Atlas news

ATLAS@Home version 2.0 with graphics

Atlas news - Tue, 08/02/2016 - 13:29
Today we have released version 2.0 of ATLAS simulation. The main addition to this version is a graphical interface which can be launched with the "show graphics" button on the BOINC manager. The interface explains a bit more about why we do ATLAS@Home, some background information on basic particle physics, some examples of what simulation looks like and links to where you can find out more about the ATLAS experiment.

Please allow the task to run for up to a minute before launching the graphics as it requires some processes to start inside the virtual machine. The interface was created by Giulio Isacchini, a student at the University of Oslo in collaboration with the rest of the ATLAS@Home team. Please ask questions, give comments and suggestions for improvements, extra features etc on the Graphics forum. The graphics are currently only available on the single-core version, we will add it to multi-core soon.

Enjoy!

EDIT:There is a small configuration issue stopping the pages loading on Mac hosts and possibly Windows hosts too. This problem will go away in the next 3-4 hours.
Categories: Atlas news

Server Upgrade

vLHCathome news - Fri, 07/29/2016 - 14:00
The server will be upgraded Monday morning. The downtime should be no longer than a few minutes.
Categories: vLHCathome news

LHC@Home - SixTrack Project News

Sixtrack news - Tue, 07/26/2016 - 10:37
The members of the SixTrack project from LHC@Home would like to thank all the volunteers who made their CPUs available to us! Your contribution is precious, as in our studies we need to scan a rather large parameter space in order to find the best working points for our machines, and this would be hard to do without the computing power you all offer to us!

Since 2012 we have started performing measurements with beam dedicated to probing what we call the “dynamic aperture” (DA). This is the region in phase space where particles can move without experiencing a large increase of the amplitude of their motion. For large machines like the LHC this is an essential parameter for granting beam stability and allowing long data taking at the giant LHC detectors. The measurements will be benchmarked against numerical simulations, and this is the point where you play an important role! Currently we are finalising a first simulation campaign and we are in the process of writing up the results in a final document. As a next step we are going to analyse the second half of the measured data, for which a new tracking campaign will be needed. …so, stay tuned!

Magnets are the main components of an accelerator, and non-linearities in their fields have direct impact on the beam dynamics. The studies we are carrying out with your help are focussed not only on the current operation of the LHC but also on its upgrade, i.e. the High Luminosity LHC (HL-LHC). The design of the new components of the machine is at its final steps, and it is essential to make sure that the quality of the magnetic fields of the newly built components allow to reach the highly demanding goals of the project. Two aspects are mostly relevant:
    specifications for field quality of the new magnets. The criterion to assess whether the magnets’ filed quality is acceptable is based on the computation of the DA, which should larger than a pre-defined lower bound. The various magnet classes are included in the simulations one by one and the impact on DA is evaluated and the expected field quality is varied until the acceptance criterion of the DA is met.


    dynamic aperture under various optics conditions, analysis of non-linear correction system, and optics optimisation are essential steps to determine the field quality goals for the magnet designers, as well as evaluate and optimise the beam performance.


The studies involve accelerator physicists from both CERN and SLAC.




Long story made short, the tracking simulations we perform require significant computer resources, and BOINC is very helpful in carrying out the studies. Thanks a lot for your help!
The SixTrack team




Latest papers:

R. de Maria, M. Giovannozzi, E. McIntosh (CERN), Y. Cai, Y. Nosochkov, M-H. Wang (SLAC), DYNAMIC APERTURE STUDIES FOR THE LHC HIGH LUMINOSITY LATTICE, Presented at IPAC 2015.
Y. Nosochkov, Y. Cai, M-H. Wang (SLAC), S. Fartoukh, M. Giovannozzi, R. de Maria, E. McIntosh (CERN), SPECIFICATION OF FIELD QUALITY IN THE INTERACTION REGION MAGNETS OF THE HIGH LUMINOSITY LHC BASED ON DYNAMIC APERTURE, Presented at IPAC 2014

Latest talks:

Y. Nosochkov, Dynamic Aperture and Field Quality, DOE review of LARP, FNAL, USA, July 2016
Y. Nosochkov , Field Quality and Dynamic Aperture Optimization, LARP HiLumi LHC collaboration meeting, SLAC, USA, May 2016
M. Giovannozzi, Field quality update and recent tracking results, HiLumi LHC LARP annual meeting, CERN, October 2015
Y. Nosochkov, Dynamic Aperture for the Operational Scenario Before Collision, LARP HiLumi LHC collaboration meeting, FNAL, USA, May 2015

Categories: Sixtrack news

Theory Tasks Available

vLHCathome news - Mon, 07/25/2016 - 12:22
Theory tasks are available again. The downtime was caused by a suspected NFS related problem that resulted in a bad batch of jobs. The submission code has been hardened to detect this scenario in the future. The maximum jobs in progress limit has been put back to 2 and we will consider increasing this limit in the very near future.
Categories: vLHCathome news

CMS Application Now Available

vLHCathome news - Fri, 07/22/2016 - 22:56
As the issues with the Theory application will probably not be fixed until after the weekend, the CMS application has been made available for everyone. Due to the slightly larger memory requirements, the the number of tasks that can be run simultaneously on a host has been reduced from 2 to 1. If for whatever reason you do not wish to run the CMS application, you can update your project specific preferences to run only the applications that you select. There will be no more tasks for Theory app until the problem has been resolved.
Categories: vLHCathome news

Theory Application job problems

vLHCathome news - Fri, 07/22/2016 - 15:10
The Theory Application looks like it is getting a batch of bad input jobs from the MCPlots server. This is causing many task errors.
We are investigating… Please be patient.
Categories: vLHCathome news

New multi-core application version 1.03

Atlas news - Mon, 07/18/2016 - 11:45
A new version of the multi-core app was released this morning which fixes the issue with the bootstrap script only setting up one core for each WU. It is recommended to abort older tasks using v1.01 if you want to take advantage of the fully working multi-core version.
Categories: Atlas news

Authentications Errors

vLHCathome news - Mon, 07/18/2016 - 11:00
The authentication service is currently down. Tasks will fail with exit status 206 EXIT_INIT_FAILURE until this is resolved. We are working to bring it back up ASP.
Categories: vLHCathome news

How can the BOINC client allocate customized CPU/Memory resources to specific applications

Atlas news - Thu, 07/14/2016 - 10:42
Some of the users might only want to give a certain ratio of their CPU/Memory to a specific application. Take the ATLAS@home Multiple core application ATLAS_MCORE for example, if you want to this app to use less than the CPU/Memory that you allow the BOINC client to use, you can do it through creating a configuration file app_config.xml in your project directory:


You can limit the MultiCore-App by using an app_config.xml.

Below is an example to limit ATLAS_MCORE to use only 4 Cores:

<app_config> <app_version> <app_name>ATLAS_MCORE</app_name> <avg_ncpus>4.000000</avg_ncpus> <plan_class>vbox_64_mt_mcore</plan_class> <cmdline>--memory_size_mb 5300</cmdline> </app_version> </app_config>

You should change these two lines to your needs:

<avg_ncpus>4.000000</avg_ncpus> <cmdline>--memory_size_mb 5300</cmdline>

Memory usage calculated by the ATLAS_MCORE app is by this formula:

memory = 1300 + (1000* NumerOfCores)

so it is 5300MB for 4 cores.


Thanks to Yeti for giving this recipe.
Categories: Atlas news

ATLAS@home releases a beta application for the multi core jobs

Atlas news - Mon, 07/11/2016 - 17:51
We have released a beta application named "ATLAS_MCORE" for the ATLAS multi-core jobs.

If you are interested in testing it on your machine, you need to allow test task in your project preference to receive jobs from this new application.

This can be enabled by login to your account on the atlasathome webpage, then click on "Your account", then click on "ATLAS@Home preferences", then check the box next to "Run test applications".

The multi-core version will check the BOINC client for both the available CPU cores(the number of CPU cores the client is configured to give to BOINC to use) and available memory size(the number of memory size the client is configured to give to BOINC to use) to decide how many cores will be allocated to one virtual machine which runs the ATLAS job.


For the ATLAS multi-core job, the relation between memory size and number of CPU cores is defined in this formula:

Total_Memory=1300MB+1000MB*Number_of_CPU_Cores

For example, a 1 core job requires 2300 MB memory, and a 2 core job requires 3300 MB memory.

The number of CPU cores which will be allocated to the virtual machine is also calculated according to this formula.
Number_of_CPU_cores=(Total_Memory-1300MB)/1000MB
The minimum number between Number_of_CPU_cores and the available CPU cores from the client is used to allocate to the virtual machine.


Currently, this test app can utilize from 2 to 8 cores of the client depending on the available CPU cores and memory size from the client.

By using multi-core jobs, we expect the runtime of jobs is close to runtime_of_single_core_job/number_of_cores, and it can significantly saves the usage of memory for clients which offers multi-cores to BOINC.
____________
Categories: Atlas news

Computation errors

vLHCathome news - Fri, 07/08/2016 - 11:28
Since we added the 64bit theory application, a number of tasks are failing with Computation Error. This is due to three reasons.

  • The need for Hardware-assisted virtualization for 64bit
  • Additional checks for issues that were not previously detected e.g. idling VMs.
  • A technology change that still requires some hardening for all the issues that we experience when running on random machines around the world.

In the past 24 hours 71.79% of hosts returned a successful task using v2619.31 but 35.38% failed tasks with 7.18% returning both successful and unsuccessful tasks. This suggests that things are working but we still have some improvements to make.

To help the situation, please could everyone periodically (no more than once per day) visit your account page and click on the Task View link in the Computing and credit section to view the results of your tasks. If you do see a computation error, click on the task to see the exit status code and the logging output.

The breakdown of failures by exit code is as follows.


  • 35.14% -1073740791
  • 27.17% 206
  • 18.84% 194
  • 6.16% 207
  • 4.35% 255
  • 3.26% -2135228415
  • 2.54% 1
  • 2.17% 203
  • 2.17% 5
  • 1.45% -186
  • 0.72% 197
  • 0.36% -2147467259
  • 0.36% -185

We will address each one of these in subsequent posts and once we have arrived at a final solution, the issue will either be fixed to stop it occurring or an entry will be added to the FAQ to explain what is going on.

Categories: vLHCathome news

CERN launches gigabit project in Kansas City

News of BOINC - Fri, 07/01/2016 - 19:57
CERN has launched the CERN+KC Gigabit Challenge, which uses gigabit optical fiber Internet connections now available in Kansas city to handle data-intensive computing problems.
Categories: BOINC news

Book about volunteer computing

News of BOINC - Thu, 06/30/2016 - 21:17
The book Community, Competition and Citizen Science by Anne Holohan documents the history of volunteer computing.
Categories: BOINC news

Disk space limit decreased to 4GB

Atlas news - Fri, 06/24/2016 - 09:30
Hi all,

To make more effective use of volunteers running ramdisks we have reduced the disk space limit from 6.5GB to 4GB. See thread here

http://atlasathome.cern.ch/forum_thread.php?id=505

We see that most tasks use at most 2.2GB so this should be safe, but please notify us of any problems related to this change.[/url]
Categories: Atlas news

Scheduler and vbox update to detect 64-bit enabled computers

vLHCathome news - Tue, 06/21/2016 - 12:56
The BOINC scheduler has been updated to detect 64 bit machines that do not have the virtualization hardware extensions enabled. Also vboxwrapper has been updated for better error handling, and vboxwrapper 26193 is now deployed for Windows and Linux for the Theory application. This setup has been tested in our dev project.

Similar updates will follow later for other applications.

Many thanks to Rom Walton for providing these changes to the BOINC code.


--The team
Categories: vLHCathome news

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