From: Kern S. <ke...@si...> - 2003-07-29 08:16:49
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Hello, On Mon, 2003-07-28 at 22:04, Robert L Mathews wrote: > At 7/27/03 8:00 PM, Kern Sibbald <ke...@si...> wrote: >=20 > >4. If bacula is running a priority 2 job and new priority 1 > > job is scheduled, followed by a priority 2 job, the new > > priority 1 job will run before the new priority 2 job. > > That is: as long as there is a high priority job waiting to > > run, no lower priority jobs will start. >=20 > Maybe I'm just not parsing this correctly, but this example doesn't seem=20 > quite right, because that's what would happen even without priorities,=20 > isn't it? Yes what I wrote would happen without priorities as long as scheduling order is maintained, which was not the case with my Semaphore code. My point was to say that even though priority 2 jobs may be running, no new ones will start if there is a higher priority job waiting. >=20 > That is, this text describes the jobs as still running in time-based=20 > order, but as I understand it, priorities give you a way to override that= =20 > order. >=20 > So, shouldn't it say something like: >=20 > 4. If bacula is running a priority 2 job and new priority 2 > ^ > job is scheduled, followed by a priority 1 job, the new > ^ > priority 1 job will run before the new priority 2 job. > Even though its time would normally make it run after the > priority 2 job, its priority takes precedence. What I wrote above is always correct, and what you suggest here is also true sometimes. It will not be true if the resources for the new priority 2 job are available -- in that case, it will be immediately started before the following priority 1 job is scheduled. If the resources are not immediately available then what you write is true. >=20 > If I've completely misunderstood, please ignore this (but perhaps=20 > consider my inability to grasp it as an indication that the description=20 > perhaps needs to be rewritten). This is no problem. I would like the manual to be clear for as many people as possible. Please take a look at: http://www.bacula.org/html-manual/dirdconf.html#Priority and if it is not clear, let me know. Best regards, Kern |