RE: edm meter

["Jeff Hill" <johill@lanl.gov>]

Ø  Using DBR_GR_XXX with value monitors could place a fair burden on the IOC though.

 

FWIW: If we extended the caeventmask.h to include a flags such DBE_GRAPHIC_META or alternatively

DBE_ALARM_LIMITS, SBE_PRECISION, etc then the database could efficiently post updates only on change.

And  of course this type of upgrade works better with the new server that allows for event queue payloads

other than the currently fixed {value, alarm status, time stamp}  tuple.

 

Jeff
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Jeffrey O. Hill           Email        johill@lanl.gov
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Message content: TSPA

 

From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of Andrew Johnson
Sent: Monday, August 23, 2010 1:37 PM
To: Till Straumann
Cc: tech-talk@aps.anl.gov
Subject: Re: edm meter

 

On Monday 23 August 2010 13:42:21 Till Straumann wrote:
> Nevertheless, if edm used the attributes it still should see a change in
> e.g., display limit the next time the value updates.

 

Using DBR_GR_XXX with value monitors could place a fair burden on the IOC though. Filling in a dbr_gr_double structure for instance requires the IOC to call the record type's get_units(), get_precision(), get_graphic_double() and get_alarm_double() routines, and the calling tree to get to them from the db_get_field() that rsrv calls is several levels deep in some cases.

 

- Andrew
--
The best FOSS code is written to be read by other humans -- Harald Welte