On 09/01/2018 04:28 AM, Fengguang Wu wrote: > To walk 1TB memory of 4k active pages, it costs 2s vs 15s system > time to scan the per-task/global idle bitmaps.
To me, that says this interface simply won't work on large systems. 2s and 15s are both simply unacceptably long. > OTOH, the per-task idle bitmap is not suitable in some situations: > > - not accurate for shared pages > - don't work with non-mapped file pages > - don't perform well for sparse page tables (pointed out by Huang Ying) OK, so we have a new ABI that doesn't work on large systems, consumes lots of time and resources to query and isn't suitable in quite a few situations.
