topic Re: jobcontroller in Operating System - OpenVMS

jobcontroller

v.saravanan_1 — Tue, 11 Jul 2006 23:17:33 GMT

can u explain breifly about jobcontroller ...

Re: jobcontroller

Steven Schweda — Tue, 11 Jul 2006 23:43:11 GMT

http://h71000.www7.hp.com/doc/index.html

http://h71000.www7.hp.com/doc/os73_index.html

(Newer HTML versions are much less convenient
to use.)

http://h71000.www7.hp.com/doc/73final/6017/6017pro.html

http://h71000.www7.hp.com/doc/73final/6017/6017pro_054.html#6017queue_mgr

Re: jobcontroller

Wim Van den Wyngaert — Wed, 12 Jul 2006 01:29:56 GMT

(from my old 5.5 internals book)

Jobctl :
. is responsible for all transactions to and from the queue file, including directing print jobs to symbionts and lexical use
. writes all the data to the accounting file
. manages all process creations (directing to loginout)

Communication with other processes is done via mailboxes.

Wim

Re: jobcontroller

Robert Gezelter — Wed, 12 Jul 2006 04:17:07 GMT

vl,

A good description can be found in the Internals and Data Structures books by Goldenberg et al. (any version will do, the general details of the Job Controller have not dramatically changed in a long time).

What in particular are you asking about?

- Bob Gezelter, http://www.rlgsc.com

Re: jobcontroller

melvyn burnard — Wed, 12 Jul 2006 04:57:22 GMT

thread title changed to make more sense, and remove confusion

Re: jobcontroller

Arch_Muthiah — Wed, 12 Jul 2006 11:56:37 GMT

Saravanan,

The Job Controller creates a new process in response to an interrupt from a terminal driver. The terminal class driver notifies the Job Controller via the Job
Controller mailbox. The Job Controller then creates a new process, and
LOGINOUT executes in the context of the newly created process. Using the
information from the user authorization file, LOGINOUT validates the
username/password combination, sets up the process characteristics
according to the UAF record, initializes the command language interpreter
environment (typically, DCL) and transfers control to it.

Aarchunan

Re: jobcontroller

Arch_Muthiah — Wed, 12 Jul 2006 12:04:05 GMT

Saravanan,

Job controller does not have any language like IBM's JCL, no need to confuse.

Also in newer versions of VMS the job controller does a security check when it begins to process the job.

As of VMS V7.3-1, the VMS job controller can set the system clock forward and back and change SYS$TIMEZONE_DIFFERENTIAL.

In a VAXcluster, users may either submit a batch job to a queue on a particular
node (not necessarily their own node), or submit a job to a cluster-wide batch
queue. Jobs on the cluster-wide queue are routed to queues attached to specific
nodes for execution. The algorithm for assigning jobs to specific nodes is a simple
one based on the ratio of executing jobs compared to the job limit of the queue.
Management of batch jobs is the responsibility of a VMS process called the
job controller. Each VMS node runs a job controller process. The process acquires
work from one or more batch queues.

For further details, There is a book "Internals and DataStructures", which covers among many other that topic.

Thanks
Archunan