Hi,
Yeah, that hardcoded 0.9 value came from Microsoft 9 years ago, and I guess nobody challenged it until now. It affects the PoolSizeVRAMPercentage value from DefaultEngine.ini, essentially being multiplied into it, so the default value of 70 makes the engine use 63% of the available VRAM for the streaming pool (unless you use D3D12.AdjustTexturePoolSizeBasedOnBudget, in which case it’s overwritten almost immediately by the code in FD3D12DynamicRHI::RHIGetTextureMemoryStats). We need to clean this up, I’ve made a ticket for it. In the mean time I think it’s safe to remove, VRAM is virtualized and the budgets are approximate so it’s probably safe to go up to the limit, or get very close to it.