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