Subject: Re: new MI/MD interface for rnd(4)
To: Colin Wood <cwood@ichips.intel.com>
From: Jason R Thorpe <thorpej@zembu.com>
List: tech-kern
Date: 06/05/2000 22:53:56
On Mon, Jun 05, 2000 at 05:50:12PM -0700, Colin Wood wrote:
> Is a 32-bit number big enough? On a sufficiently fast IA32 processor,
> that counter (assuming you're using the timestamp counter) can overflow
> within a relatively short period of time (4s on currently shipping
> processors). It is forseeable that it could overflow in less than a
> second on processors shipping within the next few years. I don't know
> enough about how often rnd.c samples, tho, so this might not be a
> problem...
Not only that, but the TSC return value is 64-bit, right? Also, the
Alpha `rpcc' intruction returns a 64-bit value, so I'd think this
would be 64-bit, at least.
--
-- Jason R. Thorpe <thorpej@zembu.com>