[LDM #BRQ-910935]: Remaking the queue every time you start the LDM & running LDM in non-daemon mode

Hi Paul,

re:
> I have two questions:
> 
> #1)  One of our LDM systems is setup to use systemd to manage the
> start/stop of the LDM.  It looks to me like it is deleting and remaking the
> queue every time there is a start/stop on the LDM.

Presumably systemd is running a startup script for the LDM.  It is in
the startup script that the LDM queue would be deleted and remade.

re:
> Other than additional
> CPU & I/O time spent on this operation, are there any other negative
> effects?

Yes.

re:
> Will duplicate products be re-requested and re-processed from
> upstream LDMs since my LDM can't tell it already got them and processed
> them?

Yes.  The only way that an LDM knows what products it has already received
by the list of products in its queue.  When the queue is deleted and
remade, the slate is wiped clean, so it will REQUEST the last hour's worth
of data.

re:
> #2)  We have some environments where we cannot run processes which do not
> terminate in a timely fashion.  Is it possible to have the LDM run and exit
> on a schedule?  Can I just:
> 
> ldmadmin stop && ldmadmin start
> 
> every 10 minutes?

You could, but that would simply add more load to your system.

re:
> What side effects should I expect from something like that?

I am not sure what bouncing the LDM would do for you other than
stopping and restarting routines that are processing by virtue
of one or more pattern-action file actions.  A better approach
would be to figure out why some of your processes are not terminating
in a timely fashion and fix the problem.


Cheers,

Tom
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Ticket Details
===================
Ticket ID: BRQ-910935
Department: Support LDM
Priority: Normal
Status: Closed
===================
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