As an example, the following provides capacity and performance information for the OPC UA server of the M262 Logic Controller. Design considerations are also provided to help you consider the optimal conditions for the performance of the OPC UA server. Of course, the performance realized by your application depend on many variables and conditions, and may differ from this example.
OPC UA server performance is determined by the system configuration, the number of symbols being published, and the percentage of symbols being refreshed.
The following table presents the number of elements small and medium configurations used for evaluating OPC UA server performance:
Elements |
Small |
Medium |
---|---|---|
TM3 expansion modules |
0 |
4 |
CANopen slave devices |
0 |
0 |
PTO functions |
0 |
0 |
HSC functions |
0 |
0 |
Profibus connections |
0 |
0 |
Modbus TCP slave devices |
0 |
0 |
Sercos devices |
0 |
0 |
Incremental hardware encoders |
0 |
0 |
Serial lines |
0 |
1 |
EtherNet/IP adapters |
0 |
1 |
EtherNet/IP Scanner devices |
0 |
18 |
Generic TCP/UDP Managers |
0 |
0 |
This table presents average read/write request times for the sample configurations and for different numbers of symbols:
Average Read/Write Request Times |
|||||||
---|---|---|---|---|---|---|---|
Configuration |
Number of Symbols |
||||||
50 |
100 |
250 |
400 |
500 |
1000 |
||
TM262L10MESE8T |
Small |
6 ms |
11 ms |
26 ms |
41 ms |
53 ms |
132 ms |
TM262L10MESE8T |
Medium |
16 ms |
29 ms |
71 ms |
117 ms |
149 ms |
350 ms |
TM262L20MESE8T |
Small |
3 ms |
5 ms |
12 ms |
18 ms |
23 ms |
56 ms |
TM262L20MESE8T |
Medium |
14 ms |
23 ms |
51 ms |
80 ms |
103 ms |
123 ms |
The following tables present the average time required to refresh a monitored set of symbols using a sampling rate of 200 ms and a publishing interval of 200 ms.
This table presents the average time required to refresh 100% of symbols for each of the sample configurations:
Average Time to Refresh 100% of Symbols |
|||||||
---|---|---|---|---|---|---|---|
Configuration |
Number of Symbols |
||||||
100 |
400 |
1000 |
|||||
TM262L10MESE8T |
Small |
204 ms |
207 ms |
218 ms |
|||
TM262L10MESE8T |
Medium |
197 ms |
209 ms |
680 ms |
|||
TM262L20MESE8T |
Small |
201 ms |
203 ms |
201 ms |
|||
TM262L20MESE8T |
Medium |
202 ms |
205 ms |
215 ms |
This table presents the average time required to refresh 50% of symbols for each of the sample configurations:
Average Time to Refresh 50% of Symbols |
|||||||
---|---|---|---|---|---|---|---|
Configuration |
Number of Symbols |
||||||
100 |
400 |
1000 |
|||||
TM262L10MESE8T |
Small |
203 ms |
204 ms |
208 ms |
|||
TM262L10MESE8T |
Medium |
195 ms |
201 ms |
623 ms |
|||
TM262L20MESE8T |
Small |
201 ms |
202 ms |
204 ms |
|||
TM262L20MESE8T |
Medium |
202 ms |
203 ms |
207 ms |
This table presents the average time required to refresh 1% of symbols for each of the sample configurations:
Average Time to Refresh 1% of Symbols |
|||||||
---|---|---|---|---|---|---|---|
Configuration |
Number of Symbols |
||||||
100 |
400 |
1000 |
|||||
TM262L10MESE8T |
Small |
201 ms |
202 ms |
202 ms |
|||
TM262L10MESE8T |
Medium |
194 ms |
196 ms |
285 ms |
|||
TM262L20MESE8T |
Small |
200 ms |
201 ms |
201 ms |
|||
TM262L20MESE8T |
Medium |
201 ms |
202 ms |
202 ms |
The OPC UA server functionality is dependent on external communication networks, external device performance, and other external parameters. Data transmitted may be delayed or other possible communication errors may arise that impose practical limits on machine control. Do not use the OPC UA server functionality for safety-related data or other time-dependent purposes.
WARNING | |
---|---|
The above tables can be useful in determining whether OPC UA server performance is within acceptable limits. Be aware, however, that other external factors influence overall system performance, such as the volume of Ethernet traffic.
To optimize OPC UA server performance, consider the following:
Minimize Ethernet traffic by setting the
to the lowest value that yields an acceptable response time.The task cycle time configured for the controller must be less than the configured value.
Configuring a
(the number of OPC UA clients that can simultaneously connect to the OPC UA server) value of greater than 1 decreases the performance of all sessions.The sampling rate determines the frequency at which data is exchanged. Tune the
value to product the lowest response time that does not adversely affect the overall performance of the controller.