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The biggest bucket is between 2^4 (16) and 2^5 (32) microseconds > with 108790 hits. With patch v2, I can do something similar in bpftrace too. :) tracepoint:exceptions:page_fault_enter / args.user_mode == true / { @start[tid] = nsecs; } tracepoint:exceptions:page_fault_exit / args.user_mode == true / { @lat[tid] = hist(nsecs - @start[tid]); } Junxuan