Xgrid@Newcastle

The Newcastle University Xgrid

Xgrid is a free software utility provided by Apple that allows any number of Apple computers to be linked together into a cluster. Creating an Xgrid across the University network will allow us to tap into the huge amount of processor power that is wasted when desktop computers are idle, particulalry at night or during weekends. The cluster is currently being utilized for bioinformatic and phylogenetic analyses that are particularly computationally intensive. However, in future the cluster should be a very useful tool for many groups across the university.

Recommended Minimum Requirements

• Mac OS X v10.3 or later
• 1GB RAM

As long as your Mac meets the requirements above, adding it to the cluster will not impair your work. If you follow the instructions below, the cluster will only utilize your CPU(s) when the computer has been idle for 15 minutes, and will be thrown off the machine as soon as someone starts to use it. Essentially the cluster will be doing most of its work at night and weekends.

For more information about Xgrid visit the Mac OS X Server webpage.

Adding Your Mac

To add your Mac to the University Xgrid, you will first need to know what version of OS X it is running. If you don't know, you can find out by clicking on the apple in the top left corner of the desktop and choosing About this Mac.

IMPORTANT!!!! Please make sure that any machines added to the cluster are set to never go to sleep. This is simply because Xgrid does not have the power to wake sleeping computers. To change sleep settings, open System Preferences (on the apple toolbar) and choose Energy Saver. Set the Put the computer to sleep when it's inactive for slider to Never. The display can be set to sleep or go to screensaver.

For OS X v10.4 (Tiger) users:

Xgrid is built into every copy of Mac OS X and Mac OS X Server 10.4 (Tiger).

1) Open System Preferences (on the apple toolbar)
2) Choose Sharing

For OS X v10.3 (Panther) users:

Xgrid does not come as part of the OS X 10.3 (Panther) operating system. However, a version of Xgrid for OS X 10.3 is available from the Apple website.

1) Download the Xgrid agent for OS X 10.3
2) When this downloads, install the software and restart the computer or log out and back in to your account
3) Open System Preferences (on the apple toolbar)
4) Choose Xgrid
5) You will be asked to configure Xgrid. This is essentially the same as described for the Tiger OS above.
Under Controller choose Use a specific controller and choose or type ires-genomics in the box
Under Agent accepts tasks choose Only when this computer is idle
Under Authentication method choose password and enter the password, which can be obtained by emailing support (at) bsu.ncl.ac.uk
6) Click on the Start button if Xgrid sharing is off.

Extras

Xgrid@Newcastle dashboard widget

We have created a Mac OS X 10.4 Dashboard widget for Tiger users to monitor the Newcastle Xgrid. The widget shows the total number of agents (machines) and processors currently in the grid, how many are working, available, unavailable and offline. It also shows the total amount of processing power being used by the cluster in the form of a speedometer. The widget was created using the Stanford Xgrid widget SDK produced by mekentosj.com

Download the widget 632Kb (requires OS X 10.4)

Contact us

The Newcastle Xgrid is administered by Dan Swan and Simon Harris. If you require support or have any questions about Xgrid@Newcastle please email support (at) bsu.ncl.ac.uk. There also is an xgrid mailing list. You can join here.