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From: John Ogness <john.ogness@linutronix.de>
To: Angelo Dureghello <angelo@kernel-space.org>,
	linux-rt-users@vger.kernel.org
Subject: Re: big rt latencies compared to non rt
Date: Tue, 11 May 2021 22:14:34 +0200	[thread overview]
Message-ID: <87im3p6n9x.fsf@jogness.linutronix.de> (raw)
In-Reply-To: <736a53fb-d80e-3faa-1a66-d40538e0fe26@kernel-space.org>

Hi Angelo,

On 2021-05-11, Angelo Dureghello <angelo@kernel-space.org> wrote:
> cyclictest --duration=180 -t=1 -m -Sp99 \
>          -i2000 -h3000 -q > histogram
>
> Average is near 16uS but there are some outside
> values near 40000, as

The first column is the latency in microseconds. The other columns
(2nd-5th) is the count of times that latency was seen for a CPU.

> 000009 000000    000000    000000    000000
> 000010 000001    000000    000002    000000
> 000011 000002    000000    000000    000000
> 000012 000023    000006    000008    000004
> 000013 001565    001504    002010    001367
> 000014 000425    001959    000649    000700
> 000015 001447    001917    001129    001415
> 000016 034084    026118    040328    032334
> 000017 040537    015000    033773    041092  <-----

CPU3 saw a latency of 17us 41092 times.

John Ogness

  parent reply	other threads:[~2021-05-11 20:14 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-11 16:00 big rt latencies compared to non rt Angelo Dureghello
2021-05-11 19:50 ` Jonathan Schwender
2021-05-11 20:14 ` John Ogness [this message]
2021-05-11 20:19   ` Angelo Dureghello

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