Re: [PATCH 0/4] new timeofday-based soft-timer subsystem

Ulrich Windl
2005-06-15T06:32:31Z

On 14 Jun 2005 at 11:11, Nishanth Aravamudan wrote:

[...]
> Would it be beneficial to encapsulate the timer_list structure? That way
> if the units change underneath and we eventually move to timer_fsecs
> (for femtoseconds), we don't need to change all the callers of
> set_timer_nsecs() again?
[...]

I don't think that we'll see a global clock with reliable femtosecond resolution
(not to talk about accuracy) in the foreseeable computer generations. Even plain
gigahertz RAM is quite some time away. So how would you distribute such high
resolution time across CPUs? As long as a syscall takes significantly longer than
1ns, or has a jitter of more than 1ns, a higher resolution clock would be just a
source of additional noise bits.

Regards,
Ulrich Windl