General

General

Where can I find help?

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See Contact Us where you'll find links to the forums, the Q&A for each project, and a contact form if you're really stuck.

We have a great community that will try to help you.

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Where can I find help?

Why are we using desktop computers instead of the Grid?

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The computing needs of the LHC, especially when it comes to comparing various theories with experimental results, are enormous. Basically, the physicists' appetite for computing power expands to fill all available resources, because there are always more theories to test than there are computers to test them with.

Since budgets are constrained, especially in these economically difficult times, access to volunteer resources is seen by CERN as a great opportunity to expand computing capacity. We'll never replace the Grid's core function of managing the data mountains, but we could augment its computing power considerably. While the LHC World-Wide Computing grid is used at full capacity to handle the analysis of LHC data, there is need for additional capacity for simulations of LHC physics, ranging from theory to simulations of detectors as well as design improvements for future accelerators.

It's also clear to everyone in our community that getting the public more directly involved in LHC physics has great outreach benefits as well. So we see this as a win-win situation. And who knows, perhaps one day we'll be able to announce an important discovery that will have been made in part thanks to the volunteers. That would be cool!

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Why are we using desktop computers instead of the Grid?

What do I need to participate in LHC@home?

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You need a computer connected to the Internet with at least 512MB of RAM and 9GB of free hard disk space. It can run Windows, MacOSX or Linux.

To run any of our LHC@home applications, you will need to install BOINC.

For other applications than Sixtrack, you will also need to install VirtualBox.

For more information, please see our installation guide.

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What do I need to participate in LHC@home?

Why contribute to LHC@home?

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By contributing to LHC@home, you are helping physicists who seek fundamental answers about our Universe.  

Your computing contributions are used to improve the instruments used by particle physicists at CERN to perform better experiments in the future.

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How am I helping scientists by contributing to LHC@home?

What is the specification for each application?

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Here are the memory and disk requirements for running a single task of an application.

Sixtrack

Requires 512MB of RAM and 1GB of free hard disk space.

Theory

Requires 630MB of RAM and 3GB of free hard disk space ( 0.8GB uncompressed disk image size ) plus ~1GB of RAM overhead for the host operating system.

ATLAS

Requires 1.4GB of RAM and 4GB of free hard disk space ( 2.2GB uncompressed disk image size ) plus ~1GB of RAM overhead for the host operating system.

CMS

Requires 2GB of RAM and 4GB of free hard disk space ( 1.7GB uncompressed disk image size ) plus ~1GB of RAM overhead for the host operating system.

LHCb

Requires 2GB of RAM and 8GB of free hard disk space ( 3.9GB uncompressed disk image size ) plus ~1GB of RAM overhead for the host operating system.

 

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What is the specification for each application?

Can I run LHC@home projects offline?

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See the forum thread here: http://lhcathome2.cern.ch/vLHCathome/forum_thread.php?id=1681. In a nutshell:

You will need to have an open internet connection while running project tasks. You cannot run the tasks if not connected to the internet.

The task starts up a VM, then the VM runs a series of tasks that each run for about 60 to 90 minutes each. At the beginning of each task inside the VM, it downloads some data, crunches the numbers, and uploads the result, then the next VM task starts and downloads more data.

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Can I run LHC@home projects offline? Or do I need my internet connection running?

Does LHC@home support GPUs?

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For the moment LHC@home does not use GPUs for running the experiments. Additionally, the GPU code could not work as we are accessing the hardware via a virtual machine.

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Does LHC@home support GPUs?

Are any of my personal data sent to CERN when I install the software?

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You will only have to provide a user name and an e-mail, nothing else is required. The information that is sent about your machine is the hardware specifications: CPU type, RAM and disk space, OS version, etc.

If you decide to leave the project, you can delete the data associated to your account from the LHC@home server.

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Are any of my personal data sent to CERN when I install the software? What information about my machine is sent?