[pbs-devel] RFC: Scheduler for PBS

[Dominik Csapak]

Hi,

great to see that you tackle this!

I read through the overview, which sounds fine, but I think that it
should more reflect the actual issues, namely limitations in memory,
threads, disk io and network.

The actual reason people want to schedule things is to not overload the system
(because of timeouts, hangs, etc.) so any scheduling system should consider
not only the amount of jobs, but how much resources the the job will/can
utilize.

E.g. when I tried to introduce multi-threaded tape backup (configurable threads
per tape job), Thomas rightfully said that it's probably not a good idea, since
making multiple parallel tape backup job increases the load by much more than before.

I generally like the approach, but I personally would like to see some
work with resource constraints, for example one could imagine a configurable
amount of available threads and (configurable?) used thread by job type

so i can set my available to e.g. 10 and if my tape backup jobs then get
4, i can start 2 in parallel but not more

Such a system does not have to be included from the beginning IMO, but the
architecture should be prepared for such things

Does that make sense?