Setting mpris module interval to 0 causes a memory leak that will eventually eat all the memory

[gunslingerfry]

Version: 0.15.0
EndeavourOS (Arch-lite rolling release): up to date as of 4/14/2026
Kernel: 6.19.11-arch1-1 #1 SMP PREEMPT_DYNAMIC Thu, 02 Apr 2026 23:33:01 +0000 x86_64 GNU/Linux
Seems to be allocating ~60k per second or so.
strace output is very active with it set to 0 but relatively calm when set to 1.
Did not collect much data when I identified it as having an RSS of 32GB, just killed it.
lsof is stable though at around 2953 handles open.
CPU sits at around 60% while idle.

Things I've tried:
Disabling mpris entirely stops memory leak
Setting mpris interval to 1 seems to stop the memory leak or at least slow it down significantly (so, temporary solution)
Tried setting everything I have that utilizes an interval, mostly things reading sys files like cpu, memory, disk, temp, etc., all to interval 0 and other than the bar flickering like a madman no hit to RSS. It does cause the CPU to peg at ~40%.

Issue did not occur prior to February. Issue presented as the bar no longer updating and being entirely unresponsive after running for a while. Did not dig into why it was happening till now.

I know interval: 0 means as fast as it can, but this did not have a noticeable impact on performance previously. Perhaps mpris was not reading the interval value before. That would explain why I set it to 0 which seems a little insane. Anyway, at least I can provide a warning to others that they should avoid mpris with interval: 0.

Thanks waybar devs!

[gunslingerfry]

I suppose it's worth noting that other modules perform poorly with interval 0 so perhaps it should not be used at all.

[praxis88]

interval 0 seems to be 1, if you set it to 1 it updates every 2 seconds.

If I set it explicitly to it's default of 0 on arch the bar doesnt load at all, and if I delete the line, the position doesnt seem to update at all.