> TBH it would be very hard to design a nonncompletely artificial benchmark were une desig make a difference compared to the other. Only way is test on an actual application and check what fits best.

I think I can agree to that.

I should note that I designed this allocator to be used on the GPU. "Size" is shared between a wavefront / SIMD unit. popcnt(exec_mask) determines how many items to alloc at a time. (if 200 threads call alloc, then they will collectively grab 200 pointers all at once, by doing size -= popcount(exec_mask)).

oh, in that contest, being able to parallelize allocation this way must be a big win. Of course it wouldn't work with a free list.