HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com> writes: > OK, rigorously, suceess or faliure of the requested free pages > allocation depends on actual memory layout at the 2nd kernel boot. To > increase the possibility of allocating memory, we have no method but > reserve more memory for the 2nd kernel now. Good enough. If there are fragmentation issues that cause allocation problems on larger boxes we can use vmalloc and remap_vmalloc_range, but we certainly don't need to start there. Especialy as for most 8 or 16 core boxes we are talking about a 4KiB or an 8KiBP allocation. Aka order 0 or order 1. Adding more memory is also useful. It is important in general to keep the amount of memory needed for the kdump kernel low. Eric
