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Date: Fri, 9 May 2025 17:15:27 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>, Kan Liang <kan.liang@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
	linux-perf-users@vger.kernel.org, Song Liu <song@kernel.org>,
	bpf@vger.kernel.org, Stephane Eranian <eranian@google.com>
Subject: Re: [PATCH v2] perf lock contention: Add -J/--inject-delay option
Message-ID: <aB5iXwMTs85nrioq@x1>
References: <20250509171950.183591-1-namhyung@kernel.org>
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In-Reply-To: <20250509171950.183591-1-namhyung@kernel.org>

On Fri, May 09, 2025 at 10:19:50AM -0700, Namhyung Kim wrote:
> This is to slow down lock acquistion (on contention locks) deliberately.
> A possible use case is to estimate impact on application performance by
> optimization of kernel locking behavior.  By delaying the lock it can
> simulate the worse condition as a control group, and then compare with
> the current behavior as a optimized condition.

Thanks, tested and applied.

- Arnaldo