Understanding Performance of Royale APIs on i.MX 8M Mini Print


A simple frame capture test at MODE_9_5FPS, using the Royale API, results in the following performance and memory consumption numbers, as running under Linux on the Emcraft i.MX 8M Mini SOM with the 38K ToF camera:

  • CPU usage by the capture process = ~22%
  • RAM usage by the capture process = ~20Mb (1.5 GB of RAM is free on the 2GB LPDDR4 SOM).

Elaborating on the CPU consumption measurements above:

  • That test is a simplified version of the PMD sampleRetrieveData Linux demo application, which receives frames as returned by the Royale APIs, and then, essentially, discards them, with no processing at levels above the Royale stack.
  • With the 22% CPU consumption by the demo process specifically, overall CPU consumption by the system is in a 22-25% range, on an otherwise idle system. Those metrics are as reported by the Linux top utility. Given the 8M Mini Quad (4 Cortex-A53 cores) chip on the Emcraft SOM, the demo consumes 5-6% of the overall CPU capacity available to Linux.