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

Subject: Re: Limits on CA message size?
From: lewis@csg.lbl.gov (Steve Lewis)
Date: Thu, 12 May 94 13:41:42 PDT
EPICS as shipped has a 16K byte buffer.  Thus you can only ship an
array of 4000 floats or ints.  At LBL we have changed the single
#define to increase this to 32K bytes to accommodate 8000 floats.  Jeff
or Marty can confirm this, but it appears and is logical that every
connection will have the bigger buffer. Thus, if you anticipate a peak
of 100 client connections for a given IOC, you will have added
16K*100=1.6MB of dynamics RAM allocation.

Note that some clients like dm carefully keep only one connection per IOC.
Others may not.  Again, Jeff and/or Andy can confirm what the demand is
for each instance of a sequencer:  It uses CA but not TCP/IP, therefore,
it may be smart enough to not need the buffer.

Steve Lewis

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