On Tue, Mar 22, 2022 at 01:47:59AM +0900, Jin-oh Kang wrote:
On Mon, Mar 21, 2022, 7:56 PM Huw Davies huw@codeweavers.com wrote: Could you provide some justification for why we should include this?
Well, I forgot to mark this as RFC. I still haven't decided how to benchmark this change effectively; feedbacks are welcome.
The rationale was that some applications were seeing frequent page faults due to writing to demand-zero pages in GDI bit blitting routines.
For a bitmap that extends over several demand-zero pages, each page access would incur a fault (in the worst scenario), resulting in significant performance drop and/or high CPU usage. This may be aggravated by non- sequential access (which usually is the case with bottom-up DIBs) or with transparent huge pages disabled.
We'd want to see some actual data on perf / CPU usage to go forward.
Huw.