[Bug 84662] Long pauses with Unreal demo Elemental on R9270X since : Always flush the HDP cache before submitting a CS to the GPU

https://bugs.freedesktop.org/show_bug.cgi?id=84662

--- Comment #54 from Andy Furniss adf.lists@gmail.com --- Created attachment 111966 --> https://bugs.freedesktop.org/attachment.cgi?id=111966&action=edit elemental stalls near end with large vram -> gtt move

Generally the new version is a bit better, it's still not right, it has glitches but they are shorter.

I have 8 Gig ram now so can run from tmpfs to exclude the glitching being caused by disk activity.

There is sometimes a new issue very near the end where there is a chance of a multi second stall corresponding to vram -> gtt move as in the screenshot.

This didn't happen at all the first couple of times I tested.

The third time only 200meg was moved the fourth is this shot.