[OpenJDK 2D-Dev] [14] RFR JDK-8235147: Release HDC from passiveDCList sooner

[Sergey Bylokhov]

Hi, Alexey.

Do we really need to pass passiveDCList everywhere, this is the only one passive list?
I guess we can remove other methods which use hwnd, like "RemoveAllDCs(HWND hWnd)"?

On 12/1/19 7:04 am, Alexey Ivanov wrote:
> Hello,
> 
> Please review the following fix for JDK:
> 
> JBS: https://bugs.openjdk.java.net/browse/JDK-8235147
> Webrev: http://cr.openjdk.java.net/~aivanov/8235147/webrev.00/
> 
> 
> When a DC becomes unused, it is moved from activeDCList to passiveDCList to be released later. It will stay in the passiveDCList until a new DC is requested for the same window or the window is destroyed.
> 
> The DCs in passiveDCList will never be used again, so we can release them as soon as another request for a DC comes in.
> 
> The test case, ManyFramesTest.java, attached to the bug creates and displays 10 frames. Then it hides the 9 frames. At this point, passiveDCList contains 9 entries. These DCs will not be released until the corresponding frame is shown and painted again or the frame is destroyed.
> 
> 
> The fix releases all DCs currently in passiveDCList when another DC is requested.
> With the fix, when running ManyFramesTest.java test case, the number of entries in passiveDCList does not grow, the list contains at most 1 entry.
> 
> Mach5 for client tests is green.
> 


-- 
Best regards, Sergey.