makedumpfile fail to strip pages

[Martin Friedrich]

Hello,

I try to identify the root-cause of an issue with kdump & makedumpfile which results in dumps to have a size of the system memory.
Kdump-tools/makedumpfile has been configured to strip most pages with the flags: " -c -d 31" and transfer the dump to an ssh target.

I'm unable to replicate the issue by crashing kernel using sysrq-triggers. As long the system crashed by sysrq-trigger, the dump has the correct size and completes successfully. 
But as soon a system crashes for other reasons, dumps get huge and fail to transfer to the ssh target due to their size.

Our servers (x64/aarch64) are running Ubuntu 22.04 with a self built kernel 6.6.32 (config attached) and makedumpfile (backported 1.7.5-3 to Ubuntu 22.04).

Am I missing something within the kernel config which could cause this behavior?


Thanks
-- Martin