The initial crashkernel size is just a default value - that was in the past a reasonable good value.
So it's not uncommon that one needs to increase the crashkernel size for a particular situation and setup. The default size is always a trade-off between reserving enough space for all possible situations and environments vs. not reserving and wasting too much space. But we already noticed that the default needs an increase nowadays, which was in general already addressed in LP#1877533. LP#1877533 is not done yet, since the approach is to do it in alignment with Debian. Nevertheless, I tend to mark this LP#1946463 as duplicate of LP#1877533 ... ** Also affects: ubuntu-z-systems Importance: Undecided Status: New ** Changed in: ubuntu-z-systems Assignee: (unassigned) => Skipper Bug Screeners (skipper-screen-team) ** Changed in: ubuntu-z-systems Importance: Undecided => High ** Changed in: linux (Ubuntu) Assignee: Skipper Bug Screeners (skipper-screen-team) => Canonical Kernel Team (canonical-kernel-team) ** Summary changed: - Ubuntu20.04.3 default crashkernel size insufficient for kdump + Ubuntu 20.04.3 default crashkernel size insufficient for kdump -- 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/1946463 Title: Ubuntu 20.04.3 default crashkernel size insufficient for kdump Status in Ubuntu on IBM z Systems: New Status in linux package in Ubuntu: New Bug description: ---Problem Description--- Unable to take a dump using kdump on host, service is enabled and correctly configured. "[ 6.110044] Kernel panic - not syncing: System is deadlocked on memory ---uname output--- Linux ilzlnx3.tuc.stglabs.ibm.com 5.4.0-81-generic #91-Ubuntu SMP Thu Jul 15 19:07:49 UTC 2021 s390x s390x s390x GNU/Linux Machine Type = S/390 ---System Hang--- Once the kdump is unsuccessful, I have to load it from the HMC. ---Debugger--- A debugger is not configured ---Steps to Reproduce--- Trigger kdump with a crash by: sysctl -w kernel.sysrq=1 echo c > /proc/sysrq-trigger *Additional Instructions for vanessa.ba...@ibm.com , finne...@us.ibm.com: -Post a private note with access information to the machine that the bug is occuring on. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1946463/+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