Speed effect caused, that some raw frames are re-used for multiple final frames. When cached final frame is freed due to memory being full, it tried to free also lower level cached frames that were used during compositing. Some lower level cached frames were already freed by different final frame and `BLI_ghash_remove()` failed. Check if key still exists in hash or if linked keys were overwritten before removing them. Reviewed By: sergey Differential Revision: https://developer.blender.org/D10909