Quick answer: Unreal RVT thrashing in the editor with tile pool overflow warnings? Either the RVT resolution is too high, the bound volume too large, or pool size too small — balance the three.

An open-world map uses an 8K RVT for the entire terrain. The tile pool overflows constantly, causing visible texture pop-in and stutter.

Pool Size in Project Settings

Project Settings → Engine → Rendering → Runtime Virtual Texture → Pool Size. Default sometimes too small for big worlds. Increase to e.g. 4096 tiles for dense outdoor scenes.

Lower Resolution per RVT

The RVT Volume has a virtual size (e.g. 256x256 tiles). Halving cuts memory by 4x. Most material blends don’t need 1cm resolution — reduce until pop is just noticeable, then back off slightly.

Multiple Smaller RVTs

Split one world-spanning RVT into several smaller ones bound to specific regions. Each can have its own pool budget; total memory is more efficiently used.

Per-Layer Compression

Use lower-bit formats for non-critical layers — BC1 instead of BC7 cuts memory in half with acceptable quality for diffuse blends.

Verifying

Stat command stat virtualtexturing shows pool fill below 90%. No texture pop-in during normal flythrough.

“RVT overflow is pool size, RVT resolution, or volume size. Balance the three.”

Profile stat virtualtexturing on every level review — pool fill is a leading indicator of impending texture stutter.