From aa2bad59fd3e3093d43177e6ee7cbc879af743fa Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Wed, 16 Sep 2026 22:07:03 -0700 Subject: [PATCH] perf Documentation: Add tip for hybrid event merging Add informative text outlining the IPC imbalances associated with merging cross-hybrid core events like cycles. Signed-off-by: Ian Rogers Assisted-by: Antigravity:gemini-3.1-pro Tested-by: Arnaldo Carvalho de Melo Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/tips.txt | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/perf/Documentation/tips.txt b/tools/perf/Documentation/tips.txt index ebf12a8c5db5..1c7b309fe6e8 100644 --- a/tools/perf/Documentation/tips.txt +++ b/tools/perf/Documentation/tips.txt @@ -66,3 +66,4 @@ For latency profiling, try: perf record/report --latency For parallelism histogram, try: perf report --hierarchy --sort latency,parallelism,comm,symbol To analyze particular parallelism levels, try: perf report --latency --parallelism=32-64 To see how parallelism changes over time, try: perf report -F time,latency,parallelism --time-quantum=1s +When merging events like cycles, different core frequencies and instructions per cycle mean the counts may not fairly reflect time spent in a function.