I am on xbuntu 15.10 and this affected me after I upgraded. I have 16GB ram and kswapd kicks in, locks it up for 10 - 30 seconds multiple times an hour. vmstat 5 shows:
1 0 1208112 569056 69376 7019032 0 0 84 347 1634 2951 25 1 73 0 0 2 0 1208072 164192 2212 6619100 14 6 163 10 2177 5029 26 3 70 0 0 0 20 2366584 204456 316 6367792 48 234926 25103 235206 6928 2748 2 8 5 86 0 1 5 3294060 151216 548 6413108 27001 193908 88306 193970 5196 6590 2 10 13 76 0 2 1 4065264 172748 3172 6488812 72246 163202 106635 163531 8388 11018 2 22 43 33 0 5 0 4806852 136160 4444 6469352 76391 153371 98650 154074 8352 9759 2 26 37 35 0 1 1 5573372 145112 816 6440936 73558 157316 87340 157662 6802 8592 2 21 44 33 0 0 4 6383744 168976 1800 6463780 74014 166143 88715 166679 6388 8669 2 27 41 31 0 1 1 7024704 146832 1924 6466112 68409 135974 78778 136382 6356 8203 1 19 42 38 0 2 0 7736084 181116 1928 6476672 56372 144775 64527 145122 8093 6853 1 16 41 43 0 0 7 8381188 197892 432 6456988 74326 159450 87829 160040 8327 8744 4 23 45 28 0 1 0 3944136 3240020 1400 6488888 9170 67 14278 74 2112 4084 22 3 69 6 0 1 0 3926636 2819400 2060 6521132 3596 0 7028 0 1848 3374 25 3 71 1 0 So you can see when it kicks in. I have made the following modifications and still have the problem: /etc/sysctl.conf: vm.swappiness=10 /etc/rc.local: # Fix khugepaged issues (20150706) echo never > /sys/kernel/mm/transparent_hugepage/defrag echo 0 > /sys/kernel/mm/transparent_hugepage/khugepaged/defrag # Another fix for khugepaged issues (20151210) echo madvise > /sys/kernel/mm/transparent_hugepage/enabled -- 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/1476211 Title: kswapd takes 100% CPU although there is no swap Status in linux package in Ubuntu: Confirmed Bug description: On a notebook with neither swap partition nor swap file (because of SSD and surplus of RAM), kswapd0 suddenly runs amok and takes 100% of CPU activity. When this happens, usually at most 5.5 of 8 GB RAM were in use, so there is no reason to swap. This happens so suddenly, that no user input is possible anymore, eg. I can barely switch to tty to kill processes that take most RAM. The processor becomes extremely hot and I can only turn the computer off and reboot. I consider this as critical and harmful to my hardware. I noticed that Ubuntu installs by default with swappiness 60. Now I changed that to 10 because I would never encounter the case that 8GB are in use, but it didn't have an effect. Expected behavior: - on systems without RAM, kswapd should never attempt to swap - if there is not enough RAM, kernel should kill processes to free up RAM - no process should be able to claim so much CPU activity, that the computer becomes unresponsive (it should always be possible to control/stop/kill processes over tty) Actual behavior: - kswapd tries to swap although there is no swap space ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: linux-image-3.19.0-22-generic 3.19.0-22.22 ProcVersionSignature: Ubuntu 3.19.0-22.22-generic 3.19.8-ckt1 Uname: Linux 3.19.0-22-generic x86_64 ApportVersion: 2.17.2-0ubuntu1.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: andreas 2368 F.... pulseaudio /dev/snd/controlC0: andreas 2368 F.... pulseaudio CurrentDesktop: Unity Date: Mon Jul 20 12:49:24 2015 EcryptfsInUse: Yes InstallationDate: Installed on 2015-06-06 (43 days ago) InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422) MachineType: LENOVO 20266 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-22-generic root=UUID=8a0dc2f3-fcf3-4e5b-8e23-1441bd36e3dc ro noprompt persistent quiet splash acpi_backlight=vendor vt.handoff=7 init=/sbin/upstart RelatedPackageVersions: linux-restricted-modules-3.19.0-22-generic N/A linux-backports-modules-3.19.0-22-generic N/A linux-firmware 1.143.1 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 10/31/2013 dmi.bios.vendor: LENOVO dmi.bios.version: 76CN31WW dmi.board.asset.tag: No Asset Tag dmi.board.name: Yoga2 dmi.board.vendor: LENOVO dmi.board.version: 31900058STD dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Lenovo Yoga 2 Pro dmi.modalias: dmi:bvnLENOVO:bvr76CN31WW:bd10/31/2013:svnLENOVO:pn20266:pvrLenovoYoga2Pro:rvnLENOVO:rnYoga2:rvr31900058STD:cvnLENOVO:ct10:cvrLenovoYoga2Pro: dmi.product.name: 20266 dmi.product.version: Lenovo Yoga 2 Pro dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1476211/+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