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From: Namhyung Kim <namhyung@kernel.org>
To: acme@kernel.org, irogers@google.com, 
 =?utf-8?q?Krzysztof_=C5=81opatowski?= <krzysztof.m.lopatowski@gmail.com>
Cc: linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
In-Reply-To: <20250206113314.335376-2-krzysztof.m.lopatowski@gmail.com>
References: <20250206113314.335376-2-krzysztof.m.lopatowski@gmail.com>
Subject: Re: [PATCH] perf: Improve startup time by reducing unnecessary
 stat() calls
Message-Id: <174007597483.1790567.5712005674301381670.b4-ty@kernel.org>
Date: Thu, 20 Feb 2025 10:26:14 -0800
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On Thu, 06 Feb 2025 12:33:15 +0100, Krzysztof Łopatowski wrote:
> When testing perf trace on NixOS, I noticed significant startup delays:
> - `ls`: ~2ms
> - `strace ls`: ~10ms
> - `perf trace ls`: ~550ms
> 
> Profiling showed that 51% of the time is spent reading files,
> 26% in loading BPF programs, and 11% in `newfstatat`.
> 
> [...]
Applied to perf-tools-next, thanks!

Best regards,
Namhyung