See attached example. I haven't studied it in detail, but it seems that when the div is half-outside the viewport, we have to repaint. The repaints themselves are light, but the texture uploads they cause are not.
Created attachment 124612 [details] Test case that repaints during animation
*** This bug has been marked as a duplicate of bug 78020 ***
Based on this, I think we should add some TRACE macros to the compositor when texture eviction occurs so we can tell the difference between invalidation-driven repainting and cache-driven repainting. David, can you do a quick patch for that?
(In reply to comment #3) > Based on this, I think we should add some TRACE macros to the compositor when texture eviction occurs so we can tell the difference between invalidation-driven repainting and cache-driven repainting. David, can you do a quick patch for that? Sure! Should we just make eviction show up in the traces or should we try to make paint show up differently in traces as a result eviction compared to invalidation?
(In reply to comment #4) > Sure! Should we just make eviction show up in the traces or should we try to make paint show up differently in traces as a result eviction compared to invalidation? Lets just get the eviction to show up. Its better than nothing. :)