Very inaccurate TSC clocksource with kernel 4.13 on selected CPUs
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Triaged
|
High
|
Unassigned | ||
Artful |
Won't Fix
|
High
|
Unassigned |
Bug Description
On kernel 4.13.0-37-generic, HP ProLiant DL380 Gen10 systems have been observed with very large clock offsets, as measured by NTP. Over the past few days on one of our production systems, we've used 3 different kernels: https:/
All of these kernels default to the TSC clocksource, which is supposed to be very reliable on Skylake-X CPUs. On 4.4 (linux-
I've produced loopstats & peerstats graphs from NTP corresponding to the dates in the pastebin above and placed them at https:/
ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-
ProcVersionSign
Uname: Linux 4.13.0-37-generic x86_64
AlsaDevices:
total 0
crw-rw---- 1 root audio 116, 1 Mar 27 18:26 seq
crw-rw---- 1 root audio 116, 33 Mar 27 18:26 timer
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.14.1-0ubuntu3.27
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CurrentDmesg:
[ 6280.259121] perf: interrupt took too long (2505 > 2500), lowering kernel.
[10463.378558] perf: interrupt took too long (3133 > 3131), lowering kernel.
[32314.949747] perf: interrupt took too long (4000 > 3916), lowering kernel.
[129804.100274] clocksource: Switched to clocksource hpet
[132747.312089] perf: interrupt took too long (5004 > 5000), lowering kernel.
Date: Thu Mar 29 07:45:22 2018
IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
Lsusb:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 0bda:0329 Realtek Semiconductor Corp.
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 0424:2660 Standard Microsystems Corp. Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: HPE ProLiant DL380 Gen10
PciMultimedia:
ProcFB: 0 mgadrmfb
ProcKernelCmdLine: BOOT_IMAGE=
RelatedPackageV
linux-
linux-
linux-firmware 1.127.24
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
WifiSyslog:
dmi.bios.date: 02/15/2018
dmi.bios.vendor: HPE
dmi.bios.version: U30
dmi.board.name: ProLiant DL380 Gen10
dmi.board.vendor: HPE
dmi.chassis.type: 23
dmi.chassis.vendor: HPE
dmi.modalias: dmi:bvnHPE:
dmi.product.family: ProLiant
dmi.product.name: ProLiant DL380 Gen10
dmi.sys.vendor: HPE
tags: |
added: canonical-is removed: artful |
tags: |
added: kernel-da-key removed: kernel-key |
tags: | added: canonical-bootstack |
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