From: Kairui Song on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1171#note_6076991...
Good suggestion, I'll update the crashkernel default values. I tried to figure out what is causing the growth of kernel-5.13.0-0.rc4.20210603git324c92e5e0ee.34, and found a lot of new things enabled in config, kgdb, kfence, and many other debug configs will all cause .bss to grow (switch back to old .config from f33, using the same kernel version and code base the .bss will be ~5M again). I'm not sure if we will turn off some of the debug options in the future but kernel is growing after all.
So for x86 and s390, we can change the crashkernel value to 0G-4G:192M,4G-64G:256M,64G-:512M (previously 1G-4G:160M,4G-64G:192M,64G-1T:256M,1T-:512M).
According to https://access.redhat.com/documentation/en-us/red_hat_enterprise_ linux/8/html/performing_a_standard_rhel_installation/system-requirements- reference_installing-rhel#check-disk-and-memory-requirements_system- requirements-reference, since we already requiring at least 1.5 GiB memory for RHEL, but I'm not sure how things work for VM deployments, will this cause more memory pressure for VMs?