[lkml]   [2001]   [Jun]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: temperature standard - global config option?
Followup to:  <>
By author: Chris Boot <>
In newsgroup:
> Well then, tell all the teachers in this world that they're stupid, and tell
> everyone who learnt from them as well. I'm in high school (gd. 11, junior)
> and my physics teacher is always screaming at us for putting too many
> decimal places or having them inconsistent. There are certain situations
> where adding a ±1 is too cumbersome and / or clumsy, so you can specify the
> accuracy using just decimal places.

This, again, is a presentation issue, and is irrelevant to the
intricacies of fixed-point arithmetric.

> For example, 5.00 would mean pretty much spot on 5 (anywhere from 4.995 to
> 5.00499), wheras 5 could mean anywhere from 4.5 to 5.499.
> Please, let's quit this dumb argument. We all know that thermistors and
> other types of cheap temperature gauges are very inaccurate, and I don't
> think expensive thermocouples will make it into computer sensors very soon.
> Plus, who the hell could care whether their chip is at 45.4 or 45.5 degrees?
> Does it really matter? A difference of 0.1 will not decide whether your
> chip will fry.

Does it really matter NOW? No. However, 1 cK is a convenient unit
and a good use of bits. Can we guarantee it won't matter in the
future, especially not on a CPU which may very well require complex
algorithms to eke out optimal performance in a thermally-challenged
environment (more than just simple trip points.) Now it gets
interesting! I have actually seen, in the lab, an algorithm which
required complex guesswork, because it required information below the
noise level of the sensor (and yes, it *is* possible to obtain that

<> at work, <> in private!
"Unix gives you enough rope to shoot yourself in the foot."
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:17    [W:0.135 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site