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Sender: Namhyung Kim <namhyung@gmail.com>
From:   Namhyung Kim <namhyung@kernel.org>
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        Yang Jihong <yangjihong1@huawei.com>, mingo@redhat.com,
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Subject: Re: [PATCH] perf data: Increase RLIMIT_NOFILE limit when open too many files in perf_data__create_dir()
Date:   Fri, 20 Oct 2023 14:21:16 -0700
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On Fri, 13 Oct 2023 07:59:45 +0000, Yang Jihong wrote:
> If using parallel threads to collect data, perf record needs at least 6 fds
> per CPU. (one for sys_perf_event_open, four for pipe msg and ack of the
> pipe, see record__thread_data_open_pipes(), and one for open perf.data.XXX)
> For an environment with more than 100 cores, if perf record uses both
> `-a` and `--threads` options, it is easy to exceed the upper limit of the
> file descriptor number, when we run out of them try to increase the limits.
> 
> [...]

Applied to perf-tools-next, thanks!