Hi Chris, Thanks for the help so far. I'm deploying a new machine right now and I'll be trying to replicate it on -48.
The way I detected it was that i'd see messaging in "dmesg" on guest similar to this: hrtimer: interrupt took 4352551231 ns In addition, when pinging the machine, you'd have a few seconds of stable pings, then unresponsive for 2-3s, and it starts responding again (with a huge delay, latency of 3s to 4s because of the delay). I will be running this machine and monitoring it closely and report on the output, however, I'd like to note that these machines have heavy KSM usage, before turning it off, one had almost ~45-50GB of deduplicated memory on a 256GB node, so I'm not sure if that plays in as a factor.. I'll report back on -48 and see what I can check Thank you, Mohammed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1435363 Title: KSM causing performance and instability issues Status in linux package in Ubuntu: Confirmed Bug description: This seems to be a bug that has regressed, I have encountered the same issue as 2 other reports: LP: #1346917 LP: #1349897 Running kernel: 3.13.0-46-generic This is replicated over many compute nodes (KVM) running OpenStack. The workaround is to disable KSM: echo 2 > /sys/kernel/mm/ksm/run This fixes the issue temporarily. --- AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Mar 22 14:30 seq crw-rw---- 1 root audio 116, 33 Mar 22 14:30 timer AplayDevices: Error: [Errno 2] No such file or directory ApportVersion: 2.14.1-0ubuntu3.7 Architecture: amd64 ArecordDevices: Error: [Errno 2] No such file or directory AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CRDA: Error: [Errno 2] No such file or directory DistroRelease: Ubuntu 14.04 InstallationDate: Installed on 2014-12-14 (99 days ago) InstallationMedia: Ubuntu-Server 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.3) MachineType: Dell Inc. PowerEdge R620 Package: linux (not installed) PciMultimedia: ProcFB: 0 EFI VGA ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-46-generic.efi.signed root=UUID=68d30a86-3c67-4691-b142-d27a459986e8 ro ProcVersionSignature: Ubuntu 3.13.0-46.79-generic 3.13.11-ckt15 RelatedPackageVersions: linux-restricted-modules-3.13.0-46-generic N/A linux-backports-modules-3.13.0-46-generic N/A linux-firmware 1.127.11 RfKill: Error: [Errno 2] No such file or directory Tags: trusty Uname: Linux 3.13.0-46-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: _MarkForUpload: True dmi.bios.date: 01/16/2014 dmi.bios.vendor: Dell Inc. dmi.bios.version: 2.2.2 dmi.board.name: 01W23F dmi.board.vendor: Dell Inc. dmi.board.version: A05 dmi.chassis.type: 23 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr2.2.2:bd01/16/2014:svnDellInc.:pnPowerEdgeR620:pvr:rvnDellInc.:rn01W23F:rvrA05:cvnDellInc.:ct23:cvr: dmi.product.name: PowerEdge R620 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1435363/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp