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<== Date ==> <== Thread ==>

Subject: RE: CA Server queue depth
From: "Jeff Hill" <[email protected]>
To: <[email protected]>, <[email protected]>
Date: Fri, 13 Feb 2009 08:29:06 -0700
> there is a queue per registered client

Correct

> The queue depth is hard coded at 16 which may not be enough in case of
> data burst.

There are actually currently two different server implementations, and two
different event queue implementations each with slightly different behavior.


> Won't is make sense to add the ability to control the depth
> of the queue on a per variable basis, something like a quality of
> service?

Yes, this appears to be a good idea, which has been considered in the past.
The primary barrier at the moment is the compile time rigid, but arguably
somewhat more efficient queuing system in the original server (in the future
it _will_ be better to be less efficient, but more flexible at runtime).
Nevertheless, perhaps the access control system should provide some
constraints on the queue depth selected by the client.

Jeff

> -----Original Message-----
> From: [email protected] [mailto:[email protected]]
> On Behalf Of Bruno Coudoin
> Sent: Thursday, February 12, 2009 2:19 PM
> To: [email protected]
> Subject: CA Server queue depth
> 
> 
> Looking at the CA Server, if I understand correctly, there is a queue
> per registered client (individualEventEntries in casEventSys.h).
> 
> The queue depth is hard coded at 16 which may not be enough in case of
> data burst. Won't is make sense to add the ability to control the depth
> of the queue on a per variable basis, something like a quality of
> service?
> 
> Bruno.


References:
CA Server queue depth Bruno Coudoin

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