From: Willy Tarreau <w@1wt.eu>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: ??? <muryo.ye@gmail.com>,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: Why ping latency is smaller with shorter send interval?
Date: Fri, 2 Oct 2020 11:56:48 +0200 [thread overview]
Message-ID: <20201002095648.GB3783@1wt.eu> (raw)
In-Reply-To: <0d8f732d-03e1-75f0-09fd-520911088c0d@gmail.com>
On Fri, Oct 02, 2020 at 11:26:00AM +0200, Eric Dumazet wrote:
> 2) Idle cpus can be put in a power conserving state.
> It takes time to exit from these states, as you noticed.
> These delays can typically be around 50 usec, or more.
This is often the case in my experience. I'm even used to starting a
busy loop in SCHED_IDLE prio on certain machines or in certain VMs
just to keep them busy, and to see the ping latency cut in half.
Willy
next prev parent reply other threads:[~2020-10-02 9:56 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-02 8:51 Why ping latency is smaller with shorter send interval? 叶小龙
2020-10-02 9:26 ` Eric Dumazet
2020-10-02 9:56 ` Willy Tarreau [this message]
2020-10-02 19:46 ` Vinicius Costa Gomes
[not found] <tencent_2AB240953B1EC86706967C25A6279EB60509@qq.com>
2020-10-02 22:24 ` David Miller
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