KWin5 memory leak?

[René J.V. Bertin]

Hi,

This is something I also noticed with KWin4 but which seems to be worse with KWin5 (v5.11.1, FW 5.38.0, Qt 5.8.0 and the Breeze windowtheme):

After a big compile job (like building QtWebKit) performed in the background (output redirected to file) with Google Chrome and Kontact running (in addition to a few Konsoles and Plasma4 [sic] desktop) I often find myself with up to 2Gb swap used. That's clearly linked to KWin5 because the swap space is freed only after I quit that app. As far as I can tell it doesn't make a significant difference here if I do some light browsing or emailing or if I let the build complete without touching the computer.

In that case a Chrome extension ("The Great Suspender") will kill my browser tabs so the only active screen output comes from Kontact's sync progress bar and my screensaver (xscreensaver running the kclock screensaver module).

Why would KWin5 be needing to allocate memory in such scenarios, which apparently it never releases until exit?

This is on a laptop with an N3150 Celeron CPU ("Cherry" graphics, i915 driver) with kernel 4.9.30 with the ConKolivas extensions. That's an embedded GPU with shared video memory, could that have anything to do with what I'm observing (I'd hope "something" is clever enough never to swap out VRAM)?

Thanks,
R.