Wednesday, September 09, 2009

Canna I no just use qsub?

Ah, the endless refrain.

Anytime a user with cluster experience is introduced to the gLite submission mechanism, some question of that order (although not always with a Scottish accent) is inevitable.

Pulling out my Human-Computer Interaction hat, I first came to the conclusion that, despite the occasional hints to the contrary, users are indeed Human. Hot on the heels of this realisation, a little bit of analysis of the gLite job submission and control tools indicated that, whilst very powerful, they work in a very different fashion to qsub.

It's not clear that qsub is in any sense a better iterface than the native command line tools, but it is clear that it is different.

The general idea was to resolve this difference by providing a different interface to grid job submission that was more familiar to users with existing experience of cluster computing. Wether it's going to be a better approch for a user without that experience is not clear; but it will make it simpler for users to use the Grid as an offload for a local cluster (i.e. use a cluster, when it's full, send the jobs to the Grid).

It turns out that the POSIX defintion of qsub isn't too far away, conceptually, from a Grid system, so all that was needed to act as an interface transalation layer was a relativly straightforward python script.

Rather than relay all the gory details here, let me direct you to the gqsub download page, with the manual.

For users on svr020, it's installed in the default path, so you can just use it. Note that to properly mirror the expected behaviour you probably want to make sure you run from within $CLUSTER_SHARED.

But to answer the original question: "Aye!"

No comments: