We recently added support for hi-res touchpads on Linux and it seems to work correctly for me even with smooth scroll enabled. What device are you using?

https://codereview.chromium.org/688253002 landed in M49 to support xinput2 for linux.

It could be that you are experiencing what's described in  issue 616995 , where we are starting an animation on a janky page when we should really be instant scrolling.

I have a patch in progress for  issue 616995 . 

Also, Could you verify that your device supports xinput2?

I'll take a look soon. Thanks for the help.

This is on a ThinkPad X240 on Fedora 24.

"xinput test-xi2 11" gives results so I assume it is an xinput2 device.

Here is the output of xinput:
$ xinput 
⎡ Virtual core pointer                    	id=2	[master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer              	id=4	[slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad              	id=11	[slave  pointer  (2)]
⎜   ↳ TPPS/2 IBM TrackPoint                   	id=12	[slave  pointer  (2)]
⎣ Virtual core keyboard                   	id=3	[master keyboard (2)]
    ↳ Virtual core XTEST keyboard             	id=5	[slave  keyboard (3)]
    ↳ Power Button                            	id=6	[slave  keyboard (3)]
    ↳ Video Bus                               	id=7	[slave  keyboard (3)]
    ↳ Sleep Button                            	id=8	[slave  keyboard (3)]
    ↳ Integrated Camera                       	id=9	[slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard            	id=10	[slave  keyboard (3)]
    ↳ ThinkPad Extra Buttons                  	id=13	[slave  keyboard (3)]


This doesn't seem related to slowness of pages. I tried this on the chrome:flags page and it makes a big difference with smooth scrolling on vs. off. When enabled, the scrolling is sloppy and sluggish and when off it's like the page is stuck perfectly to my two fingers.

The sluggishness is also apparent when doing middle-button scroll with the trackpoint.

Sorry, the model is actually ThinkPad X260.

Thanks for the details. 

I think the problem here is that we are starting smooth scroll animations for high-precision touchpads when we should really be doing instant scrolls. This may be tricky since we will need to disable the animation depending on the hardware (external mousewheel should still animate). It is also not entirely clear to me that not ever starting an animation for xinput2 is the right thing. 

We also have the same issue on Windows.

> It is also not entirely clear to me that not ever starting an animation for xinput2 is the right thing.

At the moment this would work because of r389117, only hi-res devices are handled with xinput2. This may change in the future so it's probably a bad idea to key off that, but you should be able to see what r389117 keys the decision off and use that as well to flip the "precise deltas" flag on events.

Just updated to Version 52.0.2743.82 (64-bit) on Linux.

Now I don't have hi-res scrolling at all with the touchpad or trackpoint.

I found  issue 384970  which covers that problem.

I think a solution for  issue 602769  may also work for this.

Chao's going to be doing this for Windows so it'd probably make sense to take a look at Linux after. I think we just need to set the "has high precision delta" on the chrome wheel events based on the OS API. 

This touchpad scrolling should be better after 68.0.3415.0. Please try out.