"Slow update" and "No space left on device" eventually with multiple displays #7
Description
Forum thread on "slow update", including multiple-display connection: https://forums.raspberrypi.com/viewtopic.php?t=332868
Forum thread on (what's probably) a different cause of "no space": https://forums.raspberrypi.com/viewtopic.php?t=333320
Observed: When doing nontrivial (maybe even trivial?) output to multiple displays, over time pivid starts complaining about "Slow update" events (KMS commit taking more than a frame). Over time this worsens until it starts reporting "No space left on device" (kernel rejects KMS commit), and visual artifacts become apparent and numerous.
The worsening appears to persist with the Pi in question (restarting pivid doesn't reset things), though it is reset (temporarily) by rebooting.
The easiest repro case is to run a multiple-output test like https://github.com/egnor/pivid/blob/main/test_media/jellyfish_2disp.json (from @aubilenon) and let it run for a few minutes; "Slow update" messages usually crop up after a loop or two.