Alexander Papaspyrou пишет:
Yes, it is (alas, many users -- at the moment -- know better than the available schedulers). Still, we should keep this open: either the user keeps his requirements general, such that a Resource Broker can decide; or he specifies his constraints in a way that, in the end, only a single (the one the user wants) resource matches.
The way we are testing now with ARC is to let users to specify as much (or as little) requirements as they find suitable with the same language, *and* to allow the user to select different brokering algorithms. That is, one may define a "hello world" job and select the "random" brokering algorithm. Or, one may specify a job that needs a lot of input files, and select the "data proximity" algorithm. I don't suppose there can be a universal algorithm that is optimal for every kind of task, even if the job description is so detailed that it matches only two sites (I hope the Grid will be big enough to find more than one site that satisfies the requirements). Oxana