Hello, On Sat, Feb 11, 2017 at 10:18:29AM +0800, Wei Yang wrote: > During the sparse_init(), it iterate on each possible section. On x86_64, > it would always be (2^19) even there is not much memory. For example, on a > typical 4G machine, it has only (2^5) to (2^6) present sections. This > benefits more on a system with smaller memory. > > This patch calculates the last section number from the highest pfn and use > this as the boundary of iteration.
* How much does this actually matter? Can you measure the impact? * Do we really need to add full reverse iterator to just get the highest section number? Thanks. -- tejun
