Applies To:
  • CitectSCADA 5.xx
  • CitectHMI 5.xx

Certain anti-virus software can result in trend gaps, extraneous I/O update times and slow page updates.

As an example, the Norton Anti-Virus Corporate Edition version 7.60.926, Scan Engine, on a primary I/O and trend server caused maximum I/O update times to increase from 60 ms to 14 s (!), resulting in dismal system performance.

If anti-virus software is required, find a product that results in acceptable performance.

The Citect corporate standard, McAfee, may be a good option.

Be sure to test the performance impact with actual I/O devices, i.e. not disk devices.