Public bug reported: The kdump kernel will be booted with "maxcpus=1", so no matter how many cpus this system has, only one cpu will be brought up during kdump I think. But on LPAR thymelp2, if we allocate 40 cpus on it, then kdump works just fine with 512M as crashkernel value. But if we allocate 200 cpus on it, kdump fails by trggering OOM. It has been proved that in latter situation we need 1.5G RAM reserved for kdump to let it works. Contact Information = Ping Tian Han/[email protected] Carrie Mitsuyoshi/[email protected] ---uname output--- Linux thymelp2 4.2.0-23-generic #28~14.04.1-Ubuntu SMP Thu Dec 31 13:41:19 UTC 2015 ppc64le ppc64le ppc64le GNU/Linux Machine Type = 8247-22L, LPAR ---Debugger--- A debugger was configured, however the system did not enter into the debugger ---Steps to Reproduce--- 1. configure kdump with crashkernel=512M on thymelp2 2. allcoate 40 cpus on thymelp2 and trigger kdump 3. allocate 200 cpus on thymelp2 then do kdump again *Additional Instructions for Ping Tian Han/[email protected] Carrie Mitsuyoshi/[email protected]: -Post a private note with access information to the machine that the bug is occuring on.
== Comment: #1 - Nadia N. Fry <[email protected]> - 2016-02-19 13:53:02 == Any update? == Comment: #2 - Hari Krishna Bathini <[email protected]> - 2016-02-22 03:40:05 == Mahesh posted a patch upstream which should take care of this problem http://patchwork.ozlabs.org/patch/577193/ Thanks Hari ** Affects: ubuntu Importance: Undecided Assignee: Taco Screen team (taco-screen-team) Status: New ** Tags: architecture-ppc64le bugnameltc-137281 severity-high targetmilestone-inin--- ** Tags added: architecture-ppc64le bugnameltc-137281 severity-high targetmilestone-inin--- ** Changed in: ubuntu Assignee: (unassigned) => Taco Screen team (taco-screen-team) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1560552 Title: ISST-LTE: pVM:high cpus number need a high crashkernel value in kdump To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1560552/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
