Am 18.11.2013 17:27, schrieb Anthony Liguori: > > > On Nov 18, 2013 12:20 AM, "Peter Lieven" <p...@kamp.de <mailto:p...@kamp.de>> > wrote: > > > > vnc_update_client currently scans the dirty bitmap of each client > > bitwise which is a very costly operation if only few bits are dirty. > > vnc_refresh_server_surface does almost the same. > > this patch optimizes both by utilizing the heavily optimized > > function find_next_bit to find the offset of the next dirty > > bit in the dirty bitmaps. > > > > Signed-off-by: Peter Lieven <p...@kamp.de <mailto:p...@kamp.de>> > > Can you include performance data? > I hoped that the checking 32bits (pipelined) at once compared to checking 32bits one-by-one would be convincing enough ;-)
Do you have a special test in mind? Otherwise I could try to create an artificial test case with e.g. no bits dirty, all bits dirty, only a few bits dirty (cursor update) and compare the timing for both versions. Peter
