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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260916234652.439778-5-irogers@google.com \
--to=irogers@google.com \
--cc=acme@kernel.org \
--cc=ak@kernel.org \
--cc=ak@linux.intel.com \
--cc=andi@firstfloor.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=namhyung@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.