Thanks for stopping by!
So I just bought a Pi desktop kit for my RaspberryPi 3B v1.2, which features an add-on module with an mSATA disk slot, real-time clock and power control. I installed the latest raspbian stretch (kernel version 4.9.59-v7+) on the mSATA SSD, and are now booting Raspbian from it with no SD card in the onboard card reader.
A kworker process is now constantly hogging between 8.0-13.5% CPU usage, which I think seems quite unnecessary, and it has annoying consequences, fx lagging videos with Kodi. This has never happened before I added the module.
I then tried perf (inspiration from this thread) by running sudo perf record -D 1000 -g -a sleep 20 and then sudo perf report to figure out which kernel tasks might be responsible:
But I can't figure out how to go on from there to reduce the workload. Could it be caused by the real-time clock embedded in the add-on board as __timer_delay, arch_timer_read_counter_long, and arch_counter_get_cntpct seem to have a high CPU usage? Other tasks with high load are finish_task_switch and _raw_spin_unlock_irqrestore tasks, but I can't guess what that's about.
Am I right that this is unnecessary work load of the CPU and if so, how can I reduce it?
Many thanks in advance!
