Quick answer: Unity URP RenderGraph allocation fragmenting in long sessions? Pool grows over time; allocations fail - configure pool size or recycle periodically.
10-hour play session; render graph allocations start failing; visible black flickers.
Configure pool size
URP settings > RenderGraph > pool size override. Larger; less fragmentation.
Or restart pool periodically
RenderGraph.Cleanup() at low-load moments. Pool resets.
Profile pool usage
RenderGraph debugger shows pool state. Allocations failing surface.
“Pools fragment over time. Periodic reset is the universal cure.”
For long-session games, the periodic pool cleanup is a known operational concern. Plan it.