[MC-32719] Chunk loading speed drastically decreases with Vsync

in the new 1.7 snapshots the speed at which chunks load drastically decreases when Vsync is enabled, although this should usually rather increase the speed since the game doesn't need to calculate so many frames and has more ressources for loading the chunks.
it Also depends a lot on the framerate, although it should rather be seperated so that chunks don't take ages to load in laggy areas, but just lag a little more in the beginning untill all chunks are loaded.

The attached video shows the bug in more detail.

Related issues

duplicates

MC-129 Chunks not loading surface, revealing caves, etc.

Comments

migrated 2013-09-26T22:11:53Z

Can confirm on 13w39a.
With 16 chunks render distance, to load all chunks nearby it takes...

60fps - 1.3 seconds
120fps - 2.1 seconds
Unlimited (Approximitely 350fps) - 4.2 seconds

Running Minecraft 13w39a in 1920x1080 on Nvidia GTX 660 on Windows 7

migrated 2013-11-12T20:47:15Z

I believe this may have something to do with systems that poses both integrated and discrete graphics. Reducing the frame rate may cause the system to believe the integrated graphics can handle it, and by moving graphics processes to the CPU the rendered and world loader are now sharing resources. Removing the limit means frame rate will increase until the integrated graphics max out, which would activate the discrete card, and free the CPU to load chunks.

Evidence? I can hear the GPU fan turning on when the FPS gets above ~70, and my other system which only has discrete graphics doesn't suffer from this issue. Furthermore I have found that reducing video settings helps out with the loading issue, which would indicate that reducing the system requirements for graphics is directly effecting the load times, which should only happen with an integrated graphics system.

migrated 2013-12-06T05:35:05Z

I believe this is actually linked to the Max FPS setting, not vsync (though vsync has a secondary effect).

1.7.2 suffers from slow chunk updates. After watching http://www.youtube.com/watch?v=yc565Rqt3lY and experimenting, it is clear that the Max FPS slider alone is directly linked to chunk updates.

If your Max FPS slider is set high - even if your client is totally incapable of reaching that FPS - your chunk updates will be crippled. The lower your max FPS slider, the better the chunk rate - even if you are not actually capping your FPS.

So the workaround is: set your Max FPS as low as you can tolerate.