Hari Bathini <hbathini at linux.vnet.ibm.com> writes: > On Friday 05 August 2016 12:23 AM, Hari Bathini wrote: >> On Thursday 04 August 2016 03:15 PM, Michael Ellerman wrote: >>> The code already knows how to reserve 5% based on the size of the >>> machine's >>> memory, as long as no commandline parameter is passed. So why can't we >>> just use that logic? >> >> That is the default value reserved but not a good enough value for >> every case. It is a bit difficult to come up with a robust formula >> that works for every case as new kernel changes could make the >> values obsolete. But it won't be all that difficult to find values that >> work for different memory ranges for a given kernel version. >> Passing that as range based input with "fadump_reserve_mem" >> parameter would work for every memory configuration on a >> given system, which is what this patch is trying to provide.. > > You want me to add this to the changelog on respin? I'm not really convinced. Distros are going to want to specify a fixed set of values for different memory sizes, at least that's what I've seen in the past with kdump. So I don't see why we can't just do that in the kernel with a formula based on memory size, and maybe some other information. Maybe the formula is more complicated than 5% of RAM, but it shouldn't be *that* much more complicated. cheers
