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[Bug 1531768] Re: arm64 kernel and multiple CPUs is unusably slow
I did install haveged which indeed seems to help quite a bit. But now
after having used an xlarge (8 CPU) instance for a while, I again get
hanging processes, like
ubuntu 2317 0.0 0.0 0 0 pts/0 D+ 16:14 0:00 [tail]
I used that tail on /var/log/lxd/lxd.log to see what's going on. lxd
itself stopped responding much earlier (but not in kernel "D" state,
Sorry, this is still very unspecific..
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arm64 kernel and multiple CPUs is unusably slow
Status in linux package in Ubuntu:
I created an 8 CPU arm64 instance on Canonical's Scalingstack (which I
want to use for armhf autopkgtesting in LXD). I started with wily as
that has lxd available (it's not yet available in trusty nor the PPA
However, pretty much any LXD task that I do (I haven't tried much
else) on this machine takes unbearably long. A simple "lxc profile set
default raw.lxc lxc.seccomp=" or "lxc list" takes several minutes.
I see tons of
[ 1020.971955] rcu_sched kthread starved for 6000 jiffies! g1095 c1094 f0x0
[ 1121.166926] INFO: task fsnotify_mark:69 blocked for more than 120 seconds.
in dmesg (the attached apport info has the complete dmesg).
DistroRelease: Ubuntu 15.10
Package: linux-image-4.2.0-22-generic 4.2.0-22.27
ProcVersionSignature: User Name 4.2.0-22.27-generic 4.2.6
Uname: Linux 4.2.0-22-generic aarch64
crw-rw---- 1 root audio 116, 1 Jan 7 09:18 seq
crw-rw---- 1 root audio 116, 33 Jan 7 09:18 timer
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
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:
Date: Thu Jan 7 09:24:01 2016
eth0 no wireless extensions.
lo no wireless extensions.
lxcbr0 no wireless extensions.
00:00.0 Host bridge : Red Hat, Inc. Device [1b36:0008]
Subsystem: Red Hat, Inc Device [1af4:1100]
Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Lsusb: Error: command ['lsusb'] failed with exit code 1: unable to initialize libusb: -99
PATH=(custom, no user)
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-22-generic root=LABEL=cloudimg-rootfs earlyprintk
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
UpgradeStatus: No upgrade log present (probably fresh install)
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