occasional hangs that stop trackpad and keyboard entry

trueriver

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Aug 8, 2018, 9:00:27 AM8/8/18

to qubes-users

Asus laptop UX 360 c. Trackpad, touchscreen, 4G memory (yes I know, that is small for Qubes), SSD drive.

I am getting occasional hangups where actions on the keyboard and trackpad are ignored. Sometimes this is a few seconds, sometimes longer, very occasionally it is a cup of tea job.

One guess as to what is happening is that the trackpad driver in Dom0 gets some vital part swapped out, and it is a while before it is swapped back in. To test this guess, is there a way I can lock the trackpad driver in real memory?

Another guess is that this is due to an unwanted "takeover" by the unwanted touch screen. How can I permanently disable the touch screen in Dom0 to test this guess.

IF either guess turns out to be right, it will of course be elevated to have been a hypothesis all along ;)

awokd

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Aug 12, 2018, 3:33:16 PM8/12/18

to trueriver, qubes-users

My guess would be that 4G of RAM too; it's probably swapping like you
said. You can try to fine tune your max RAM allocations per VM, but 8G
should really be considered the minimum.

trueriver

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Jan 1, 2020, 7:31:34 AM1/1/20

to qubes-users

I had problems with the trackpad on the install of R 4.0 over a year ago, and occasional trackpad hangs when Dom0 was busy. My guess at the time was that this was due to running Qubes on only 4gb ram.

So, still on an Asus 360 but now with 8gb ram, I was shocked to find that there were still issues during install (had to use a USB mouse on R 4.0.2rc3).

On the installed system the problem of the trackpad pointer hanging whenever Dom0 is busy seemed worse, than on R 4.0 (this is subjective, as I have no data to back up my impression). Not a show stopper but frequent enough to be annoying.

I found that the problem goes partly away if I keep sys-usb running even when not needed.

To make it go away altogether I found I needed to alter xen.cfg in the EFI files, to make the Max ram equal the min. 1024M works for me as a value for both figures. Keep a backup copy of the original file in case this fix dies not work for you.

Just to be clear, the problem only resolved when both those fixes were applied together.

My next post will detail how I came to this conclusion and my thoughts on what is happening. As at least one other person is facing this issue at present, I thought I would post this brief workaround before the detail. I want to be at my laptop to type in the detail, rather than swiping it in on this phone screen :(