Experimental Physics and
Industrial Control System

[email protected] (Jeff Hill) · Mon, 10 Jul 2000 19:05:45 -0600

> I am finding poor response times for the portable CA server.

I am unable to reproduce that here. Please run the program 
"catime <pv name>" against a pv in your server and send the 
result. The catime program can be built by typing "gnumake catime" in 
base/src/ca/O.<workstation arch>.

With both servers the _average_ round trip time for a get is 
typically less than 2 mS on slow machines and less 1 mS on fast hosts. 
Your 3 Ms may be also including the time required to search for the 
channel and build the TCP/IP circuit to the IOC? 

I have attached a catime result from when catime was running
on NT 4.0 400 MHz pentium III and the "excas" example portable server
was running on a Solaris 5.6 Sparc Ultra-2. The "sync get test" 
below measures the average round trip time for a get.

Jeff

E:\users\hill\R3.13.1.patch\epics\base\src\ca\O.WIN32>catime fred
EPICS attached to winsock version WinSock 2.0
Process attached to Com.dll version EPICS Version 3.13.2
Process attached to ca.dll version EPICS Version 3.13.2
Testing with 10000 channels named fred
search test
Thread attached to ca.dll
Elapsed Per Item =   0.00014530 sec,     6882.3 Items per sec, 1.2 Mbps
Search tries per chan - mean=1.468200 std dev=1.621909 min=1.000000 max=11.00000
0
channel name=fred, native type=2, native count=1
        pend event test
Elapsed Per Item =   0.00004600 sec,    21739.1 Items per sec
float test
        async put test
Elapsed Per Item =   0.00008775 sec,    11396.0 Items per sec, 1.5 Mbps
        async get test
Elapsed Per Item =   0.00003581 sec,    27925.2 Items per sec, 3.8 Mbps
        synch get test
Elapsed Per Item =   0.00086000 sec,     1162.8 Items per sec, 0.2 Mbps
string test
        async put test
Elapsed Per Item =   0.00008802 sec,    11361.1 Items per sec, 1.9 Mbps
        async get test
Elapsed Per Item =   0.00003696 sec,    27056.3 Items per sec, 4.5 Mbps
        synch get test
Elapsed Per Item =   0.00086000 sec,     1162.8 Items per sec, 0.2 Mbps
integer test
        async put test
Elapsed Per Item =   0.00008786 sec,    11381.7 Items per sec, 1.5 Mbps
        async get test
Elapsed Per Item =   0.00003546 sec,    28200.8 Items per sec, 3.8 Mbps
        synch get test
Elapsed Per Item =   0.00085000 sec,     1176.5 Items per sec, 0.2 Mbps
free test
Elapsed Per Item =   0.00003420 sec,    29239.8 Items per sec, 4.0 Mbps
Process detached from ca.dll version EPICS Version 3.13.2
Process detached from Com.dll version EPICS Version 3.13.2
EPICS released winsock version WinSock 2.0

> -----Original Message-----
> From: jennings [mailto:[email protected]]
> Sent: Monday, July 10, 2000 3:31 PM
> To: [email protected]
> Subject: Performance of portable CA server ?
> 
> 
> I am finding poor response times for the portable CA server.  Doing a 'get'
> for a PV on an IOC gives a typical response time of about 3 msec, rising to
> about 10 msec max.  Doing a 'get' for a PV on a workstation running the
> 'excas' example PV server gives a typical response time of about 100 msec,
> rising to 600 msec max.  I get the same behavior under Solaris and under
> Linux, neither workstation is heavily loaded.
> 
> Can anyone explain the difference, and is there anything I can do to improve
> the performance?
> 
> Epics versions R3.13.1, R3.13.2
> Workstation(s) Sparc 20 w/ Solaris & 450 MHz PII w/ Red Hat Linux 6.2
> 
> 

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System