[3dprinter-general] Bug#1118139: Bug#1118139: slic3r-prusa: flaky autopkgtest 'check-gui' on at least riscv64

[Gregor Riepl]

Hi,

> The 'check-gui' autopkgtest for slic3r-prusa intermittently fails on
> ci.debian.net on riscv64:
> 
> https://ci.debian.net/packages/s/slic3r-prusa/testing/riscv64/

Two things in those logs stood out to me:
There were debug messages about wxTreeCtrl, which seem to have occurred in other instances versions, but they may not actually be a problem.

358s 10:06:12 PM: Debug: window wxTreeCtrl at 0x2ac9816aa0 ("treeCtrl") lost focus even though it didn't have it
358s 10:06:12 PM: Debug: window wxTreeCtrl at 0x2ac9816aa0 ("treeCtrl") lost focus even though it didn't have it

The other remarkable thing was the overall duration of the test:

328s Waiting for 30 seconds to ensure Prusa Slicer has not crashed
358s Dumping windows list

On amd64, the whole test suite needs significantly less time:

  40s Waiting for 30 seconds to ensure Prusa Slicer has not crashed
  70s Dumping screenshot

> This test runs as root, uses su to drop privileges, starts a window
> manager and the app, waits for an arbitrary 30 seconds and takes
> screenshots. This seems sufficiently high-complexity that it is going to
> be difficult to make it 100% reliable, especially on slow machines like
> riscv64 where 30 seconds might not be enough.

Judging from the reported duration, this may very likely be the case.

I tried running the test in a qemu container, since I currently don't have any RISC-V hardware at my disposal for testing (I have access to the cfarm, but they're rather impractical to use from a packager perspective). The test reported success, although it didn't terminate properly - but this may be a problem with qemu or my particular test container.

Would you suggest we increase the test timeout, or simply mark the GUI test as flaky?
I think it's at least worth a try to see if a 60s (or more) timeout would fix the issue.

Your other suggestion seem worthwhile, but I doubt they will fix the issue.

Regards,
Gregor