UNIX batch queue not FIFO?

[Doug Kratky]

Our user is complaining that "batch" is not choosing jobs to run "first in first out". Is that expected? How are "batch" jobs scheduled? Is there more detailed documentation on batch beyond what I can find in man pages?

[Pete Randall]

Doug,

You've probably read the man page, but it seems worth quoting:

"batch schedules a job for execution immediately, or as soon as system
load levels permit."

So, unless the system load levels interfere, it should be first come, first serve.


Pete

[Dave Hutton]

I think looking at the man pages that this file:
/var/adm/cron/queuedefs

defines how many jobs can be running at a time, depending on what queue they are in.

Dave

[Tim Sanko]

I had a user who referred to at jobs as batch jobs. At jobs run when scheduled, more or less. Check if that is what he means...

Tim

[Doug Kratky]

The users are using the "batch" command. I've verified that jobs are not being run first-in, first-out. For example, the 25th job in the queue can run before the 10th job.

[doug mielke]

or are they referring to jobs in general. The unix queue is definitely not FIFO.

My favorite description of the Unix queue was as a 'Mob scene, where the biggest and baddest get what they want", and not that little process that's been waiting patiently, at least until he gets old.