From: "Jörn Engel" <joern@wohnheim.fh-wedel.de>
To: Dan Parks <Dan.Parks@CAMotion.com>
Cc: SA <no_spam@ntlworld.com>, linux-kernel@vger.kernel.org
Subject: Re: interrupt latency ?
Date: Mon, 10 Feb 2003 16:43:04 +0100 [thread overview]
Message-ID: <20030210154304.GA1973@wohnheim.fh-wedel.de> (raw)
In-Reply-To: <1044889126.1438.460.camel@localhost>
On Mon, 10 February 2003 09:58:46 -0500, Dan Parks wrote:
>
> Do you happen to have a program (or kernel module...) that times these
> latencies? I've been trying to generate statistics about these kinds of
> latencies, and have yet to be happy with any of my tests.
That should be impossible to do. :)
Write a simple handler for parport or so, that is called when line #1
toggles from low to high and responds by pulling line #2 from low to
high.
Now hook up a signal generator and an oszilloscope and measure the
time from signal generation to the physical reaction.
This way you get all the latency, not just the small amount you can
measure inside the kernel.
Jörn
--
Everything should be made as simple as possible, but not simpler.
-- Albert Einstein
next prev parent reply other threads:[~2003-02-10 15:33 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-02-07 18:50 SA
2003-02-10 13:58 ` Jörn Engel
[not found] ` <1044889126.1438.460.camel@localhost>
2003-02-10 15:43 ` Jörn Engel [this message]
2003-02-10 16:20 ` Richard B. Johnson
2003-02-10 17:08 ` Jörn Engel
2003-02-10 18:30 ` Richard B. Johnson
2003-02-11 11:59 ` Jörn Engel
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