AnsweredAssumed Answered

Strange clEnqueueMapImage/clEnqueueUnmapMemObject behaviour

Question asked by boxerab on Dec 18, 2016
Latest reply on Jan 12, 2017 by boxerab

Windows 10

Latest Crimson Driver

RX 470


I created a 1024x1024 image and mapped it with the CL_MAP_WRITE flag,

but I only mapped a 64x64 region in the image.


Using the returned pointer, I filled the entire 1024x1024 image , and called clEnqueueUnmapMemObject.


I expected only the 64x64 region to be copied from host to device, but in fact the entire 1024x1024 region gets copied.


Is this expected behaviour ? This doesn't seem very efficient to me: if I only map a 64x64 region, then only this region

should get copied to the card.