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

Subject: Re: R3.13
From: Jeff Hill <[email protected]>
To: Chip Watson <[email protected]>
Cc: Nick Rees <[email protected]>, [email protected]
Date: Thu, 20 Feb 1997 17:08:59 -0700
Chip Watson wrote:
> 
> Nick,
> 
> >Thus I seem to have a problem relating to R3.13, and one of the symptoms
> >is likely to be caused by Channel Access messages not being delivered for
> >substantial perods of time.
> 
> Are you getting "dropped events" messages on that IOC's console?  If
> so, the messages are being lost, most likely due to insufficient CPU
> resources.  Channel access is starved first (reference: the "warm"
> discussion of last month on priorities), and events are then discarded.
> 



If the IOC is 100% saturated then the system must degrade.
Our design choice was to degrade in a controlled fashion. We
decided that internal activities in a robust distributed system 
must take priority over external activities. The channel access 
_server_ is starved first. Client activity runs at a higher priority.
Its true that the IOC will discard intermediate CA events (monitors) if
the server does not have enough CPU, the network is down, or
the client does not have enough CPU. 


Jeff

-- 
______________________________________________________________________
Jeffrey O. Hill                 Internet        [email protected]
LANL MS H820                    Voice           505 665 1831
Los Alamos, NM 87545 USA        FAX             505 665 5107


References:
Re: R3.13 Chip Watson

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