Re: [v1 0/9] Early boot time stamps for x86

From: Pasha Tatashin
Date: Wed Mar 22 2017 - 20:00:57 EST


Hi Peter,

Thank you for looking at this patchset.

Yes, I am certain it is 0 or near 0 on reset on this machine. Because, I actually wondered about it, and used stop watch as an alternative way to verify the result, twice.

While, I suspect it is often the case that on reset tsc is 0, it is not really import, as the offset value is not the important part of the project. The important part is that we can cover the whole Linux boot process with timestamps, and know where spend time, and avoid regressions in the future.

Thank you,
Pasha

On 2017-03-22 16:28, Peter Zijlstra wrote:
On Wed, Mar 22, 2017 at 04:24:16PM -0400, Pavel Tatashin wrote:
- early tsc offset is 549s, so it took over 9 minutes to get through POST,
and GRUB before starting linux

Lol, how cute. You assume TSC starts at 0 on reset.