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From: Breno Leitao <leitao@debian.org>
To: Usama Arif <usama.arif@linux.dev>
Cc: davem@davemloft.net, edumazet@google.com, horms@kernel.org,
	 kuba@kernel.org, kuniyu@google.com,
	linux-kernel@vger.kernel.org,  netdev@vger.kernel.org,
	pabeni@redhat.com, willemb@google.com, shakeel.butt@linux.dev,
	 hannes@cmpxchg.org, riel@surriel.com, kernel-team@meta.com
Subject: Re: [PATCH] net: use sync wakeups for socket error reports
Date: Wed, 8 Jul 2026 08:25:48 -0700	[thread overview]
Message-ID: <ak5rH-SWjiqR6MVe@gmail.com> (raw)
In-Reply-To: <20260708133815.3419465-1-usama.arif@linux.dev>

On Wed, Jul 08, 2026 at 06:38:15AM -0700, Usama Arif wrote:
> Measured on a 176-core EPYC 9D64 host running a Meta production
> workload, bpftrace on tracepoint:ipi:ipi_send_cpu with a kstack filter
> attributed the sock_def_error_report -> ep_poll_callback ->
> try_to_wake_up -> ttwu_queue_wakelist -> __smp_call_single_queue
> chain to 16,326 IPIs/min.

I am interested in why so many sock_def_error_report().

That's seems a lot for genuine socket errors (RST/ICMP) on a healthy
host, so I suspect these aren't errors at all?

Can you share the full stack above sock_def_error_report()?

  reply	other threads:[~2026-07-08 15:26 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-08 13:38 [PATCH] net: use sync wakeups for socket error reports Usama Arif
2026-07-08 15:25 ` Breno Leitao [this message]
2026-07-08 16:08   ` Usama Arif
2026-07-08 16:32     ` Eric Dumazet

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