I had a similar transparent huge pages issues some time back -- the symptoms were incomprehensible spikes in CPU usage sometimes. Apparently this had something to do with memory allocation pressure when my Python processes restarted. However I thought these were perhaps weird power throttling issues which meant CPU was performing at a lower performance (explaining why a normal startup took 1 cpu minute instead of 0:10 seconds).
I should have spotted this by looking at the split between user and system CPU: when the THP problem happened SYS% spiked, but I was looking at a dozen processes pegged at 100% CPU.
I eventually tracked this down via "perf top" which lets you see what everything on the system is doing: both kernel and user space symbols are tracked. I saw significant kernel-space work in an odd memory-related symbol and found someone else with the same problem.
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I had a similar transparent huge pages issues some time back -- the symptoms were incomprehensible spikes in CPU usage sometimes. Apparently this had something to do with memory allocation pressure when my Python processes restarted. However I thought these were perhaps weird power throttling issues which meant CPU was performing at a lower performance (explaining why a normal startup took 1 cpu minute instead of 0:10 seconds).
I should have spotted this by looking at the split between user and system CPU: when the THP problem happened SYS% spiked, but I was looking at a dozen processes pegged at 100% CPU.
I eventually tracked this down via "perf top" which lets you see what everything on the system is doing: both kernel and user space symbols are tracked. I saw significant kernel-space work in an odd memory-related symbol and found someone else with the same problem.