Nova API (NeoForge 1.21.1) # warning this mod will not be updated and or have bug fixes so this mod will most likely be the one causing issues in your modpack.

Key Features

Chunk streaming & caching – Hot/warm chunk caches with configurable TTLs, per-dimension executors, and batched flushes to reduce churn during exploration or automation. Compression level and codec are configurable for disk and network payloads.
Async task system – A configurable worker pool (cores − 1 by default) with per-tick application caps and optional timeouts to offload CPU-heavy work without starving the main thread.
Performance advisor loop – Observes tick spikes, generates mitigation actions, and logs guidance when the tick budget is exceeded.
Memory-safe region cache – Dimension-aware, TTL-governed cache with eviction to prevent chunk retention leaks.
Admin/Dev commands – /novaapi memory reports heap usage and cache pressure; /novaapi tasks sanity-checks the background scheduler.
Analytics & background services – Initializes async chunk streaming, background task scheduler, and safe shutdown hooks on server lifecycle events.

/novaapi memory – Shows heap usage and region cache metrics (requires permission level 2).
/novaapi tasks – Verifies the background executor is alive without holding level references.

when world starts there will be some fps drops since the system is starting up wait 1-3 min and it will be smooth.