On my windows (Surface Pro2), Krita's animation player seems to be broken.

https://drive.google.com/file/d/1jNN_mM ... MLfLk/view

I pressed play button,but it doesn't update canvas correctly.
It occurs in any new document,
and I reinstalled Krita,but it has a same problem yet.

Please share the actual file so people can take a look; animation is not broken, lots of people are making animations all day long every day, so it's probably something to do with how you set up your file.

OK,It's here.

https://drive.google.com/open?id=1LFxHE ... E5REjxGauP

I opened this file on other PC, and it is broken.
It may occurs in small document like 16x16.

There was a similar problem, some time ago, noted by someone who was making a small animated sprite. There, as here, the individual frames of the animation were not played properly during the animation; either no change at all or some incorrect change.

Using a fairly recent 4.2.0 pre-alpha appimage, I've just recreated the animation by tomoakio and found exactly the same problem. I tried scaling the image up to 32 x 32 (nearest neighbour interpolation) and that played ok (as does the animation by tomoakio after scaling up). After scaling back down to 16 x 16 it had a frozen animation but showing a different fixed frame. (Does this suggest an animation cache related problem?)

I tried a simple small 'growing plant' animation on a 128 x 128 transparent layer over a white background using a one pixel brush and that had frame replay problems until I thickened up the lines using a larger brush, after which it played ok. I noticed similar behaviour at other image sizes.

I also created a similarly 'frozen' animation on a 128x 128 white layer that could be unfrozen by painting large blobs of colour in areas away from the animated 'growing plant'. If these colour blobs were then overpainted in white, then those frames were not replayed properly but froze.

It seems that krita has difficulty with an animated layer that only has a small amount of 'painted content' in it. A 16 x 16 image will always have only a small amount of paint in it. Whether or not this is the 'cause' of the problem is a matter for developers to figure out; this is just what I've observed in some simple experiments.