Hi, Daniel Egger <de@xxxxxxxxxx> writes: > Your change dramatically changed the picture. That surprises me, but there is obviously a lot I have to learn about threads. Thanks for testing my changes. > However dithering on is still loosing quite a bit on this SMP > machine.... Dithering makes heavy use of GRand and as long as the random number generator is shared between the threads... I wonder if it actually makes sense to add the overhead of per-thread data initialization or if we should rather replace the use of a random number generator with a pre-calculated dither pattern. That would improve the single-threaded case as well. Sven
