System performance – Rockwell Automation 1789-L10_L30_L60 SoftLogix 5800 System User Manual User Manual

Page 248

Advertising
background image

248

Rockwell Automation Publication 1789-UM002J-EN-P - December 2012

Appendix E

System Performance Tuning Guidelines

System Performance

There are a number of configurable parameters in the SoftLogix 5800 controller
that affect the overall system performance of your personal computer. These are
the parameters.

Table 12 - Parameters for Improved Performance

SoftLogix Parameter

Description

Continuous task dwell time

By default this value is 10 ms. Your application should be structured such that the continuous task contains programs
that are not time critical so that you can adjust the dwell time to a value as large as possible. For time critical tasks use
Periodic type tasks and be prudent in the number of periodic tasks and the configured period.

Periodic save interval

This parameter should also be set as large as possible to a value that is appropriate for your application. Every time the
periodic save runs, SoftLogix high priority tasks consume CPU time to save tag values and the user program to the
hard disk.
This setting does not affect the storing of online edits to the hard disk. Edits saved at:
Next periodic save interval
User-initiated save
Controller shutdown

You can also observe the execution of the periodic save in the Windows Task Manager. It is possible that if you set the
time interval short and have a large number of tags that the periodic save runs continuously. This in itself is not an
anomaly, however as a goal, keep the overall CPU use below 80% on a continuous basis. This leaves headroom for other
Windows applications to run properly. If your system cannot be tuned to achieve this, then it is recommended you use
a dual Pentium personal computer or upgrading to a faster Pentium processor.

CPU affinity

Use the CPU affinity setting on a dual Pentium processor personal computer to balance the overall system
performance. You can:
Run control on one CPU and leave the second CPU for other Windows applications.
Install two SoftLogix controllers in the virtual chassis and set the affinity of each to a different CPU.

For the best overall performance, especially when using integrated motion, use one SoftLogix controller in the virtual
chassis on a single CPU system.

EtherNet/IP connections

The total number of connections from an EtherNet/IP port in a SoftLogix controller depends on the performance of the
computer running the controller. As you increase the number of connections, the performance of the computer
decreases.

The spikes show when the
periodic save is running.

Advertising