Things may have improved a little since I reported the issue. Effects are less pronounced, mainly intermittent pointer and screen freeze lasting a few seconds at a time and difficulty starting new programs or restoring minimised windows, rather than the complete lock-ups previously experienced. However, there may just be another factor that I've not been able to identify as yet.
-- 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/1486997 Title: Copying a large file causes user interface to stop responding Status in linux package in Ubuntu: Incomplete Bug description: If you run, for example, `cp file1 file1-copy` with several GB of data, give it a minute, then the user interface stops responding and the mouse stops moving. There are occasional glimmers of response but it's like watching a video one frame at a time. I would expect the user interface to continue to work barring the occasional interruption. When the copy completes, or if you can interrupt it, the user interface works normally again. Despite the specific title, which I'll explain next, the command you use doesn't matter. Any heavy and prolonged disc activity does it. Ironically, running `ubuntu-bug kernel` to report this problem caused the mouse and UI to freeze for a few seconds. Scheduled backups also cause it. So, why the specific title? This has been reported by other user and myself before but in more general terms. Those reports are drowned in comments by frustrated users clutching at straws to the point where it's hard to see where they're going. I thought it might be helpful to limit this bug report to a very specific and easily testable example so that we don't get side-tracked working around what is probably a kernel scheduling issue. This is not an isolated or new problem. I've been using ubuntu since 2008 on several different machines and it's always been a problem. Maybe it's a little worse now, maybe not. In any case, there's no point bisecting the kernel as it's not a regression. The problem also affects the terminal. If you switch to another TTY the log-in takes ages, and usually doesn't complete until the heavy disk activity has finished. This can be extremely frustrating when you don't know which process is making mischief and you want to use a terminal to find it and stop it. It is possible to alleviate the problem by disabling swap. I did this on the hunch that processes were being frozen while memory was paged in from the disk. Unfortunately my current workload makes this solution impractical. What's odd is that the problem occurs even when there's several GB of memory to spare. After re-enabling swap you need to wait a little before re-testing to reproduce the problem. I've also tried other kernel schedulers. None help. I'm a software developer and happy to get my hands dirty, but sadly I'm quite unfamiliar with the kernel. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.16.0-45-generic 3.16.0-45.60~14.04.1 ProcVersionSignature: Ubuntu 3.16.0-45.60~14.04.1-generic 3.16.7-ckt14 Uname: Linux 3.16.0-45-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.12 Architecture: amd64 CurrentDesktop: Unity Date: Thu Aug 20 12:21:59 2015 InstallationDate: Installed on 2015-07-13 (37 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) SourcePackage: linux-lts-utopic UpgradeStatus: No upgrade log present (probably fresh install) --- ApportVersion: 2.14.1-0ubuntu3.19 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/pcmC0D0p: phill 2715 F...m pulseaudio /dev/snd/controlC0: phill 2715 F.... pulseaudio CurrentDesktop: Unity DistroRelease: Ubuntu 14.04 HibernationDevice: RESUME=UUID=fab564c9-5c8a-439f-8b9d-a10c8a4b75ad InstallationDate: Installed on 2015-07-13 (165 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) MachineType: System manufacturer V-P5G45 Package: linux (not installed) ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.16.0-56-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 3.16.0-56.75~14.04.1-generic 3.16.7-ckt20 RelatedPackageVersions: linux-restricted-modules-3.16.0-56-generic N/A linux-backports-modules-3.16.0-56-generic N/A linux-firmware 1.127.19 RfKill: 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no Tags: trusty Uname: Linux 3.16.0-56-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip libvirtd lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 05/18/2009 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 0405 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: V-P5G45 dmi.board.vendor: ASUSTeK Computer INC. dmi.board.version: Rev 1.xx dmi.chassis.asset.tag: Asset-1234567890 dmi.chassis.type: 3 dmi.chassis.vendor: Chassis Manufacture dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0405:bd05/18/2009:svnSystemmanufacturer:pnV-P5G45:pvrSystemVersion:rvnASUSTeKComputerINC.:rnV-P5G45:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion: dmi.product.name: V-P5G45 dmi.product.version: System Version dmi.sys.vendor: System manufacturer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1486997/+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
