As of at least mesa 19.3/bfac462d929 on a Vega 64:

Running obs-studio, even without starting a broadcast, will begin a seemingly
exponential memory leak.  It will be fine for a few minutes, until it rapidly
begins consuming what appears to be kernel memory (nothing attributed to app,
but total usage skyrockets).  With 32G of ram I exhaust system memory after
about three minutes, but the OOM killer doesn't know what to take down as OBS
itself remains low in the list.  This can then murder the whole system.

However, killing OBS causes most of the memory to be freed.  I say most because
after reproducing on a fresh boot, there were apparently a few gigabytes of
unaccounted for memory that never returned.  Subsequent repros of the bug on
that same boot returned to the same baseline, however.  Some caching mechanism
gone wrong?

I've noticed this going back at least a few weeks, but haven't a proper bisect.
 It should be very easy to reproduce, and happens on both Vega 64 systems I
have available.

Steps to reproduce, may not all be necessary but I confirmed this does it from
a fresh state:
- Launch obs-studio
- Enable Studio Mode by clicking the button the right
- Add two sources: "desktop capture" (select any monitor) and a single "Image"
source (any image)
- Press Fade/Cut up top to make that state live.  No need to actually start
recording/broadcasting.
- Wait a few minutes or until your system hangs.  Memory usage will appear
stable for at least a full minute before taking off unprompted.  It will not be
attributed to the app, however, being apparently kernel memory.

Reproduces with 19.3 - bfac462d929
Does not reproduce with 19.1.4

Kernel versions 5.2.8/5.2.11 same behavior