NFS kernel server creates a kworker with 100% CPU usage, then hangs randomly
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
This concerns the server edition of 14.04. I have set up a NFS server. Once I attach at least one client, one kworker process starts to use 100% CPU. The runaway kworker returns to idle when I reset the NFS server daemon with "service nfs-kernel-server stop" followed by "service nfs-kernel-server start". With the nfs kernel server stopped, the CPU remains idle. With the nfs kernel server running, as soon as one client requests a connection, the kworker process jumps to 100% CPU again.
After some random time, the nfs kernel server no longer accepts requests from clients. Restarting the service allows clients to reconnect. The syslog shows no relevant information.
Configration: The svcgssd is not running. I played with various configurations (enabling/disabling NFSv3 and NFSv4), but it makes no difference.
I tried to nable event debugging:
#> echo workqueue:
#> cat /sys/kernel/
and found the following kernel trace in a tight loop:
[...]
kworker/2:1-86 [002] d... 161940.910668: workqueue_
kworker/2:1-86 [002] d.s. 161940.910674: workqueue_
kworker/2:1-86 [002] d... 161940.910675: workqueue_
kworker/2:1-86 [002] d.s. 161940.910681: workqueue_
kworker/2:1-86 [002] d... 161940.910682: workqueue_
kworker/2:1-86 [002] d.s. 161940.910688: workqueue_
kworker/2:1-86 [002] d... 161940.910689: workqueue_
kworker/2:1-86 [002] d.s. 161940.910695: workqueue_
kworker/2:1-86 [002] d... 161940.910696: workqueue_
kworker/2:1-86 [002] d.s. 161940.910702: workqueue_
[...]
At present, I have to consider NFS fubar.
Thanks,
Mark
ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-
ProcVersionSign
Uname: Linux 3.13.0-24-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.13.0-24-generic.
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.14.1-0ubuntu3.1
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/
CRDA: Error: [Errno 2] No such file or directory: 'iw'
Card0.Amixer.info: Error: [Errno 2] No such file or directory: 'amixer'
Card0.Amixer.
Date: Thu May 22 22:48:48 2014
HibernationDevice: RESUME=
InstallationDate: Installed on 2014-05-12 (10 days ago)
InstallationMedia: Ubuntu-Server 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
IwConfig:
eth0 no wireless extensions.
lo no wireless extensions.
MachineType: Gigabyte Technology Co., Ltd. GA-990XA-UD3
ProcEnviron:
TERM=xterm
PATH=(custom, no user)
XDG_RUNTIME_
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcFB: 0 nouveaufb
ProcKernelCmdLine: BOOT_IMAGE=
RelatedPackageV
linux-
linux-
linux-firmware 1.127.2
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
WifiSyslog:
dmi.bios.date: 10/13/2011
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F9
dmi.board.name: GA-990XA-UD3
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSof
dmi.product.name: GA-990XA-UD3
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
tags: | added: stella-oem-highlight |
This change was made by a bot.