I had left gnome-disks performing a long SSD benchmark and noticed it when apt autocomplete would spike the real time bandwidth graph from ~180 MB/s to ~280 MB/s. Spamming Tab for autocomplete would have an immediate feedback on the graph.
I figured that obviously the same thing happened with all CPU intensive tasks, below are two screenshots where you can see the difference when running a stress test on one core for the duration of the SSD benchmark.
Could this be caused by some SoC clock source used by the core frequency affecting the PCIe performance?
There were reports where using a high power 12v USB-PD power supply would increase ssd bandwidth from 180 to 300 MB/s but here I was using a simple 5.1v 3A power supply (official Raspberry PI USB-C supply).