From: Robert Dewar <robert_dewar@my-dejanews.com>
Subject: Re: Context Switching
Date: 1999/05/11
Date: 1999-05-11T00:00:00+00:00 [thread overview]
Message-ID: <7h9nl5$9hr$1@nnrp1.deja.com> (raw)
In-Reply-To: 37383ab3@eeyore.callnetuk.com
In article <37383ab3@eeyore.callnetuk.com>,
"Nick Roberts" <nickroberts@callnetuk.com> wrote:
> In another thread I said some processors could do a context
switch in a few
> 'picoseconds'. I am grateful to Keith Thompson pointing out
to me that I
> meant 'nanoseconds'. It'll happen one day, of course, but not
until they've
> solved the problem of those pesky tunnelling electrons.
Sorry!
You have to be careful here. The raw hardware speed for a
context switch is not what is interesting, what is interesting
is the time for executing the COMPLETE pthread call that causes
the context switch.
For example, the actual raw hardware speed for changing a task
priority is probably just a single store instruction, but it may
well take hundreds or even thousands of instructions to filter
through the necessary kernel machinery to get to the point of
issuing that store!
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next prev parent reply other threads:[~1999-05-11 0:00 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-05-05 0:00 delay until and GNAT isaac buchwald
1999-05-05 0:00 ` David C. Hoos, Sr.
1999-05-05 0:00 ` dennison
1999-05-06 0:00 ` Buz Cory
1999-05-06 0:00 ` Robert Dewar
1999-05-06 0:00 ` delay until and GNAT - expand isaac buchwald
1999-05-07 0:00 ` Roger Racine
1999-05-08 0:00 ` dewar
1999-05-10 0:00 ` Roger Racine
1999-05-10 0:00 ` Joel Sherrill
1999-05-11 0:00 ` isaac buchwald
1999-05-11 0:00 ` dennison
1999-05-12 0:00 ` Robert Dewar
1999-05-11 0:00 ` Robert Dewar
1999-05-11 0:00 ` dennison
1999-05-10 0:00 ` Context switching (was: delay until and GNAT) Nick Roberts
1999-05-11 0:00 ` Robert Dewar
1999-05-11 0:00 ` Robert Dewar
1999-05-11 0:00 ` Tarjei Tj�stheim Jensen
1999-05-11 0:00 ` Robert Dewar
1999-05-11 0:00 ` David Brown
1999-05-10 0:00 ` delay until and GNAT - expand Roger Racine
1999-05-11 0:00 ` Robert Dewar
1999-05-11 0:00 ` dennison
1999-05-11 0:00 ` Robert Dewar
1999-05-12 0:00 ` delay until and GNAT - where to get the info isaac buchwald
1999-05-12 0:00 ` Robert Dewar
1999-05-11 0:00 ` delay until and GNAT - expand Roger Racine
[not found] ` <rracine.14.00 <rracine.15.000968A0@draper.com>
1999-05-11 0:00 ` Robert Dewar
[not found] ` <rracine.14.00 <rracine.17.0007DA28@draper.com>
1999-05-12 0:00 ` dennison
1999-05-12 0:00 ` Roger Racine
1999-05-06 0:00 ` delay until and GNAT Roger Racine
1999-05-10 0:00 ` Nick Roberts
1999-05-11 0:00 ` Context Switching Nick Roberts
1999-05-11 0:00 ` Robert Dewar [this message]
1999-05-11 0:00 ` Robert I. Eachus
1999-05-12 0:00 ` dennison
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