There are two types of performance counters, run-time event performance counters for the AI Engine modules and run-time memory counters for memory modules. These performance counters can be configured to track a variety of events in the AI Engine and the memory module. Various features like error-correction code (ECC) scrubbing, event trace and profiling can use these performance counters. Performance counters count occurrences of a given event in a profile configuration. The profile feature offers several different configurations of these performance counters that can be dynamically applied at run-time to collect various profiling statistics.
No changes are required in PS host code when using performance counters. These counters can be configured, read and collected at run-time while the design is executing in hardware. The following table lists the number of performance counters that are available at different configurations.
| Event Trace Used? | ECC Scrubbing Used? | Counters Available for Profiling | |
|---|---|---|---|
| Core Module | Memory Module | ||
| No | No | 4 | 2 |
| No | Yes | 3 | 2 |
| Yes | No | 2 | 0 |
| Yes | Yes | 1 | 0 |
The ECC scrubbing is ON by default and it can be turned ON/OFF using the AI Engine compiler option. For more information, see AI Engine Compiler Options. When ECC scrubbing is enabled, three counters are available for profiling.
When performance counters are used for ECC scrubbing, event trace and profiling in the same execution, allocated performance counters cannot meet the requirements of all the requested features at the same time. The following warning messages indicate this situation.
