Dypsis is an optimization mod with a focus on improving client-side rendering performance. It contains both improvements for vanilla and targeted optimizations for mods.
Vanilla
Framebuffer Optimization Strategy
Conservative mode optimizes framebuffer blitting with a more efficient method.
Aggressive mode makes the game directly render to the default framebuffer to skip the blitting process altogether.
HUD Batching: Draw HUD elements in batches to improve performance.
Smart Entity Outline Rendering: Skips entity outline (a.k.a. glowing effect) rendering when there is no entity visible with outline.
Mods
Ender IO: Batched rendering for conduits, significantly improves performance when you have a handful of conduits in the world.
The One Probe: Skips redundant GL calls.
Advanced
(WIP) Modern Rendering Pipeline: Very experimental and immature replacement of the vertex array usage in Tessellator. Utilizes VAO and DSA to improve performance.