NAPOPC Server 002
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Q: NAPOPC DA server
uses 95-99% of CPU time independent of the polling rate that I
specify in lookout. Is
this a known problem and do you have a
method to fix this?
¡@
Ans:
A default group's update rate setting of our
prior version is setting to 10 ms, so it uses too much
system
resources. Versions after 2.02, are setting to 100 ms to reduce the usage of
system
resources.
Note: The specification for OPC defines that if
a client software passes the group's update-rate with
0, it indicates
the server would use the fastest practical rate.
After a version of 2.02, if a client assigns a
update-rate value that less than 10ms, the NAPOPC
server will set the update rate
to 100 ms as the default update value.
if ( Update Rate < 10 ) Update Rate =
100;
Note: Users have to adjust the group's
update rate dependent on user's system environment, for
example:
CPU performance, communication baud rate, local or remote
accessing and how many
modules and tags to read...etc..
Written by Gary
Date:2004/9/7 |