Stuff for benchmarking and stability testing.
Prime95 is mprime on Linux. This page has notes on test sizing for hitting the CPU vs RAM: https://www.rieselprime.de/ziki/Prime95
In the overclocking community, a rule of thumb is often used to determine how long to run Prime95: test the CPU (8 kB FFT) for 10 hours and the memory (4096 kB FFT) for 10 hours, and if the system passes, there is a high chance that it is stable.