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[IDD #KEO-635989]: Is there any known way to 'throttle' LDM java daemons, upon system reboot?



Hi Robert,

re:
> We're trying to see if there's some way of throttling the number of
> java procs that LDM seems to spawn, when the host server is down for
> a period of time and then attempts to get 'caught up' on all the data
> that it missed pulling during the outage window.

Point of clarification:

The LDM-6 is not written in Java, so none of its processes are
java procs.  If you are seeing a number of java procs at LDM startup,
they must be run as "actions" defined in an LDM pattern-action file
(e.g., ~ldm/etc/pqact.conf).

The way to limit the load that the LDM puts on your machine
after an extended quiescent period is to restrict the backlog
of data that it requests on startup.  This is done by specifying
the '-o offset' flag in the 'ldmadmin start' invocation.  For
instance:

ldmadmin -o 1 start

This says to start the LDM but only ask for data that is 1 second
old or newer.  NB: the minimum value for 'offset' is 1; specifying
'0' (zero) is the same as not specifying the offset at all, and
the default is to request 360 seconds (1 hour) of data.

re:
> Right now, upon server restart, it appears that LDM launches as many java
> procs as the server OS can handle (sometimes even completely crippling
> the machine until LDM is 'caught up' to the missed data window).

Again, the only way that the LDM would start java procs is if your
pattern-action file(s) invokes java procedures.

re:
> Is there a setting in ldm.conf, or a flag for the java line command that
> would limit the number of spawned procs that LDM can initiate?

No.  That would be contrary to the purpose of the application.

re:
> Thanks for any help you can offer.

Try changing your LDM startup script to request less data using the 'o'
flag.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: KEO-635989
Department: Support IDD
Priority: Normal
Status: Closed