OS-6735: ::scalehrtime could be more precise

Details

Issue Type:Bug
Priority:4 - Normal
Status:Resolved
Created at:2018-03-03T03:25:25.824Z
Updated at:2019-08-30T10:58:37.658Z

People

Created by:Former user
Reported by:Former user
Assigned to:Former user

Resolution

Fixed: A fix for this issue is checked into the tree and tested.
(Resolution Date: 2019-08-20T12:19:24.768Z)

Description

For quite some time, we've had the ::scalehrtime dcmd (see OS-770). However, this is imprecise with respect to large values (e.g., TSC reads) because it doesn't follow the same algorithm as the kernel (which only converts values less than the tsc_tick interval). ::scalehrtime should mimic this, using a delta against tsc_last if the value to convert is closer to tsc_last than it is to 0.

Comments

Comment by Jira Bot
Created at 2018-03-05T19:34:42.301Z

illumos-joyent commit 0aebb1a717eb0d01fb3bad7889984fdfcba97451 (branch master, by Bryan Cantrill)

OS-6735 ::scalehrtime could be more precise
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: David Pacheco <dap@joyent.com>