RE: slow caput from R3.14.11 client to R3.14.9 IOC

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

Hi Mark,

I ran some quick tests of R3.14.11 on my pc.
I see a maximum throughput closer to a million puts 
per second when doing routine tests of the ca client library 
against the ca example server (excas), but this is not connecting 
and disconnecting the channel with each put. I can also
connect around 50000 channels per second. This is probably
with a debug (no optimization) build.

It takes about 8 seconds to run a script that does 100 caput 
command line requests against the example server on my workstation.

Jeff
______________________________________________________
Jeffrey O. Hill           Email        johill@lanl.gov
LANL MS H820              Voice        505 665 1831
Los Alamos NM 87545 USA   FAX          505 665 5107

Message content: TSPA


> -----Original Message-----
> From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-
> bounces@aps.anl.gov] On Behalf Of Mark Boots
> Sent: Thursday, October 14, 2010 2:20 PM
> To: tech-talk@aps.anl.gov
> Subject: slow caput from R3.14.11 client to R3.14.9 IOC
> 
> Hi all,
> 
> We've noticed at the CLS that channel access puts (caput) from a
> default R3.14.11 build (linux-x86) to a 14.9 IOC are very slow.  As a
> test, we ran a shell script with ~100 caput (command line) calls; it
> took ~ 24 seconds to complete using the 14.11 version of caput, and
> only 6s for the 14.9 version.
> 
> Asynchronous caputs (using the channel access library, instead of the
> command line) seem to be even slower -- sometimes taking over a minute
> for the IOC to respond to all 100 puts.
> 
> We're still debugging to see if this is a peculiarity of the IOC.  I'm
> just wondering if anyone has seen similar issues involving channel
> access between different EPICS versions?  Any suggestions for tools or
> methods to help diagnose the problem?
> 
> Best regards,
> -Mark
> 
> 
> =======================================
> Mark Boots
> 
> Dept. of Physics and Engineering Physics
> University of Saskatchewan
> 
> Rm 202 Physics Building
> 116 Science Place,
> Saskatoon SK S7N 5E2
> Canada
> 
> (306) 261-4162
> 
> =======================================