[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From pt...@cn.ibm.com 2016-04-04 21:50 EDT--- (In reply to comment #42) > The documentation is not fixed and recommends the usage of 5% of your whole > memory as the min_free_kbyte is documented at: > > https://wiki.ubuntu.com/ppc64el/ > Recommendations#Min_free_kbytes_kernel_configuration Hi, On some situations, such as bug 139648, we have to use a large min_free_kbytes vaule to prevent oom killer being triggered when running stress tests. So looks like a large min_free_kbytes is needed. And I think this bug isn't a problem of min_free_kbytes too large. It is because that when performing kdump, the value is read from /etc/sysctl.conf. If we can change this (don't using min_free_kbytes of /etc/sysctl.conf), this bug can be fxied. Thanks. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From pt...@cn.ibm.com 2016-03-28 21:29 EDT--- Hi, This bug only occurs when min_free_kbytes=312721 is written in /etc/sysctl.conf. If we didn't write it into /etc/sysctl.conf and just set it with "sysctl min_free_kbytes=312721", then this bug won't be triggered when triggering kdump. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From ru...@us.ibm.com 2016-03-28 16:01 EDT--- Minor changes to the kernel handling of user_min_free_kbytes appears to be the ideal solution here since it would have benefits outside of the kdump environment. Currently, it appears that it is too easy to manually set a completely inappropriate value. Elsewhere, the value is capped at either 65536 or 5% of lowmem, but it appears that the user provided value is not run through the same sanity checks (see init_per_zone_wmark_min() as an example). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From carri...@us.ibm.com 2016-03-15 12:53 EDT--- (In reply to comment #33) > Yes, I have started to work on a possible solution. Do you have any update on the solution to this issue? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From pt...@cn.ibm.com 2016-03-16 23:03 EDT--- (In reply to comment #35) > Hello, > > After investigating the issue, it turns out that an adequate solution is not > possible without sensible modification to the kernel. > > As explained before, the kernel allows for the definition of a > vm_free_kbytes which is above the size of the total memory available. > > This parameter is enable very early during the boot phase and cannot easily > be disabled. > > kdump is not at fault here since it doesn't even get a chance to run prior > to when the OOM starts killing processes. > > The only workaround is to remove the definition of vm.vm_free_kbytes from > the /etc/sysctl.conf file so the kernel dump may proceed. Looks like kdump of ubuntu uses the default initrd of production kernel and it will read the /etc/sysctl.conf. I think we can add some code to figure which context is before trying to read it and don't use it when running kdump. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From carri...@us.ibm.com 2016-01-28 12:28 EDT--- (In reply to comment #31) > Hello, > > The context here is that your modification of vm.min_free_kbytes brings the > value of vm_free_kbytes above the available memory defined by the > crashkernel boot parameter. > > A definitive fix for this situation requires some non trivial development, > which will take time. > > I can only suggest for the time being to raise the value of crashkernel for > your system, in order to alleviate the problem until a definitive solution > is implemented. Hello, Canonical. Just for clarification, is this something you'll be working to fix? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From nad...@us.ibm.com 2016-01-22 17:18 EDT--- Any update to this bug? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From pt...@cn.ibm.com 2016-01-11 22:10 EDT--- This bug can be reproduced on 14.04.4. I'd like to change the version to 14.04.4. Thanks. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From pt...@cn.ibm.com 2016-01-11 20:55 EDT--- Hi, This problem occurs on the system which has been set a high vm.min_free_kbytes value in the /etc/sysctl.conf. On those systems, kdump will fail. The workaround is set the value each time by running 'sysctl'. This isn't convenient. We'd like to have a solution that the value of vm.min_free_kbytes in production system's /etc/sysctl.con doesn't affect running of kdump. Thanks. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kexec-tools/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 1528101] Comment bridged from LTC Bugzilla
--- Comment From hepat...@in.ibm.com 2015-12-28 10:39 EDT--- Hi Launchpad, Can you please take a look and assign appropriate developer to solve this bug? Thanks for your support..! - Henish -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1528101 Title: ISST-LTE: kdump failed: second kernel booting hangs after /scripts /init-bottom when large min_free_kbytes value being set To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1528101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
