On Wed 31-10-18 16:19:45, Kuo-Hsin Yang wrote: [...] > The previous mapping_set_unevictable patch is worse on gem_syslatency > because it defers to vmscan to move these pages to the unevictable list > and the test measures latency to allocate 2MiB pages. This performance > impact can be solved by explicit moving pages to the unevictable list in > the i915 function. As I've mentioned in the previous version and testing results. Are you sure that the lazy unevictable pages collecting is the real problem here? The test case was generating a lot of page cache and we simply do not reclaim anon LRUs at all. Maybe I have misunderstood the test though. I am also wondering whether unevictable pages culling can be really visible when we do the anon LRU reclaim because the swap path is quite expensinve on its own. -- Michal Hocko SUSE Labs
