From: Ian Rogers <irogers@google.com>
To: irogers@google.com, acme@kernel.org, namhyung@kernel.org
Cc: ak@kernel.org, ak@linux.intel.com, andi@firstfloor.org,
linux-perf-users@vger.kernel.org
Subject: [PATCH v3 4/9] perf Documentation: Add tip for hybrid event merging
Date: Wed, 16 Sep 2026 16:46:47 -0700 [thread overview]
Message-ID: <20260916234652.439778-5-irogers@google.com> (raw)
In-Reply-To: <20260916234652.439778-1-irogers@google.com>
Add informative text outlining the IPC imbalances associated with
merging cross-hybrid core events like cycles.
Signed-off-by: Ian Rogers <irogers@google.com>
Assisted-by: Antigravity:gemini-3.1-pro
---
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.
--
2.55.0.1082.g2b9226bbc0-goog
next prev parent reply other threads:[~2026-09-16 23:47 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-16 6:52 [PATCH v2 0/9] perf report/top: Add opt-in --hybrid-merge Ian Rogers
2026-09-16 6:52 ` [PATCH v2 1/9] perf evlist: Implement evlist__can_merge_hybrid using first_wildcard_match Ian Rogers
2026-09-16 7:02 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 2/9] perf ui hist: Add support for aggregated total_period and merging entries Ian Rogers
2026-09-16 7:04 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 3/9] perf tools: Expose opt-in --hybrid-merge Ian Rogers
2026-09-16 7:04 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 4/9] perf Documentation: Add tip for hybrid event merging Ian Rogers
2026-09-16 6:59 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 5/9] perf evlist: Toggle merged_hybrid_group properly in enable/disable Ian Rogers
2026-09-16 7:06 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 6/9] perf tools: Add TUI hints for --hybrid-merge Ian Rogers
2026-09-16 7:01 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 7/9] perf config: Add core.hybrid-merge to configure event merging Ian Rogers
2026-09-16 6:59 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 8/9] perf test: Expand tests for --hybrid-merge Ian Rogers
2026-09-16 7:04 ` sashiko-bot
2026-09-16 6:52 ` [PATCH v2 9/9] perf test: Isolate test suite from user .perfconfig natively Ian Rogers
2026-09-16 7:08 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 0/9] perf report/top: Add opt-in --hybrid-merge Ian Rogers
2026-09-16 23:46 ` [PATCH v3 1/9] perf evlist: Implement evlist__can_merge_hybrid using first_wildcard_match Ian Rogers
2026-09-16 23:58 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 2/9] perf ui hist: Add support for aggregated total_period and merging entries Ian Rogers
2026-09-16 23:57 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 3/9] perf tools: Expose opt-in --hybrid-merge Ian Rogers
2026-09-16 23:57 ` sashiko-bot
2026-09-16 23:46 ` Ian Rogers [this message]
2026-09-16 23:48 ` [PATCH v3 4/9] perf Documentation: Add tip for hybrid event merging sashiko-bot
2026-09-16 23:46 ` [PATCH v3 5/9] perf evlist: Toggle merged_hybrid_group properly in enable/disable Ian Rogers
2026-09-16 23:53 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 6/9] perf tools: Add TUI hints for --hybrid-merge Ian Rogers
2026-09-16 23:53 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 7/9] perf config: Add core.hybrid-merge to configure event merging Ian Rogers
2026-09-16 23:57 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 8/9] perf test: Expand tests for --hybrid-merge Ian Rogers
2026-09-16 23:53 ` sashiko-bot
2026-09-16 23:46 ` [PATCH v3 9/9] perf test: Isolate test suite from user .perfconfig natively Ian Rogers
2026-09-16 23:57 ` sashiko-bot
2026-09-17 5:06 ` [PATCH v4 0/9] perf report/top: Add opt-in --hybrid-merge Ian Rogers
2026-09-17 5:07 ` [PATCH v4 1/9] perf evlist: Implement evlist__can_merge_hybrid using first_wildcard_match Ian Rogers
2026-09-17 5:14 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 2/9] perf ui hist: Add support for aggregated total_period and merging entries Ian Rogers
2026-09-17 5:16 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 3/9] perf tools: Expose opt-in --hybrid-merge Ian Rogers
2026-09-17 5:16 ` sashiko-bot
2026-09-18 20:31 ` Arnaldo Carvalho de Melo
2026-09-18 20:51 ` Ian Rogers
2026-09-17 5:07 ` [PATCH v4 4/9] perf Documentation: Add tip for hybrid event merging Ian Rogers
2026-09-17 5:10 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 5/9] perf evlist: Toggle merged_hybrid_group properly in enable/disable Ian Rogers
2026-09-17 5:13 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 6/9] perf tools: Add TUI hints for --hybrid-merge Ian Rogers
2026-09-17 5:14 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 7/9] perf config: Add core.hybrid-merge to configure event merging Ian Rogers
2026-09-17 5:16 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 8/9] perf test: Expand tests for --hybrid-merge Ian Rogers
2026-09-17 5:18 ` sashiko-bot
2026-09-17 5:07 ` [PATCH v4 9/9] perf test: Isolate test suite from user .perfconfig natively Ian Rogers
2026-09-17 5:17 ` sashiko-bot
2026-09-18 20:40 ` [PATCH v4 0/9] perf report/top: Add opt-in --hybrid-merge Arnaldo Carvalho de Melo
2026-09-18 21:58 ` Arnaldo Carvalho de Melo
2026-09-18 22:07 ` Ian Rogers
2026-09-18 22:11 ` Ian Rogers
2026-09-18 23:04 ` Arnaldo Melo
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