Bug 1677218

Summary: RFE: support for extended PTP_SYS_OFFSET ioctl in chrony
Product: Red Hat Enterprise Linux 8 Reporter: Miroslav Lichvar <mlichvar>
Component: chronyAssignee: Miroslav Lichvar <mlichvar>
Status: CLOSED ERRATA QA Contact: Ondrej Mejzlik <omejzlik>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 8.0CC: atragler, mkolaja, mlichvar, omejzlik, qe-baseos-daemons, thozza
Target Milestone: rcKeywords: FutureFeature
Target Release: 8.0   
Hardware: Unspecified   
OS: Unspecified   
Fixed In Version: chrony-3.5-1.el8 Doc Type: No Doc Update
Doc Text:
Story Points: ---
Clone Of: 1643983 Environment:
Last Closed: 2019-11-05 22:24:17 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1677215    
Bug Blocks: 1677213    

Description Miroslav Lichvar 2019-02-14 10:02:32 UTC
+++ This bug was initially created as a clone of Bug #1643983 +++

Description of problem:
A new ioctl is needed to enable a more accurate synchronization of the system clock with HW timestamping (bug #1643974). When available, the ioctl needs to be supported by chrony.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1. run chronyd as an NTP client with HW timestamping and look for hwclock messages in the debug output:
    chronyd -d -d "server $LOCAL_NTPSERVER minpoll 2 maxpoll 2" \
       'hwtimestamp *' |& grep 'hwclock.*err='

Actual results:
2018-10-20T19:19:44Z hwclock.c:191:(HCL_AccumulateSample) HW clock samples=16 offset=-1.859570e-08 freq=2.936241e-05 raw_freq=3.643518e-05 err=1.193500e-06 ref_diff=7.251244e+03

It depends on the NIC, PCIe slot, and other things, but usually the reported error is about 0.7-2.5 microseconds.

Expected results:
Reported error smaller than 0.5 microsecond at least for some supported NICs.

Comment 7 errata-xmlrpc 2019-11-05 22:24:17 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.