450d060e8f
Commit 47c09d6a9f67("bpftool: Introduce "prog profile" command")
introduced "bpftool prog profile" command which can be used
to profile bpf program with metrics like # of instructions,
This patch added support for itlb_misses and dtlb_misses.
During an internal bpf program performance evaluation,
I found these two metrics are also very useful. The following
is an example output:
$ bpftool prog profile id 324 duration 3 cycles itlb_misses
1885029 run_cnt
5134686073 cycles
306893 itlb_misses
$ bpftool prog profile id 324 duration 3 cycles dtlb_misses
1827382 run_cnt
4943593648 cycles
5975636 dtlb_misses
$ bpftool prog profile id 324 duration 3 cycles llc_misses
1836527 run_cnt
5019612972 cycles
4161041 llc_misses
From the above, we can see quite some dtlb misses, 3 dtlb misses
perf prog run. This might be something worth further investigation.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201119073039.4060095-1-yhs@fb.com
Linux kernel
============
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