From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Luiz Capitulino <lcapitulino@redhat.com>
Cc: linux-rt-users@vger.kernel.org,
Marcelo Tosatti <mtosatti@redhat.com>,
williams@redhat.com, riel@redhat.com
Subject: Re: cyclictest abstime vs. reltime
Date: Thu, 18 Dec 2014 09:22:19 +0100 [thread overview]
Message-ID: <20141218082219.GC10857@pengutronix.de> (raw)
In-Reply-To: <20141217151650.6ee5649c@redhat.com>
Hello Luiz,
On Wed, Dec 17, 2014 at 03:16:50PM -0500, Luiz Capitulino wrote:
> So, my question boils down to: is there a relevant difference between
> the two modes? Why isn't reltime the default mode?
I don't know, but I think in reality you want abstime. Consider a process
that does something with items that pass at your machine on a belt conveyor.
Then you need to handle one item (say) each 200ms and using reltime means
that your latencies add and even with a latency of 1µs you'd miss
approx. 1 item per year.
Best regards
Uwe
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Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
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next prev parent reply other threads:[~2014-12-18 8:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-17 20:16 cyclictest abstime vs. reltime Luiz Capitulino
2014-12-18 8:22 ` Uwe Kleine-König [this message]
2014-12-18 10:04 ` John Ogness
2014-12-18 14:33 ` Luiz Capitulino
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