AtlasSpigot 1.21.11 - build 2

AtlasSpigot 1.21.11, built on Leaf ver/1.21.11.

The main change: a real memory leak fix

fixes.vanilla-bug-fix.mc-301114 is now on, and on this version that's a genuine bug fix rather than a tweak.

On 26.2 the same setting only swaps how an already-capped list is trimmed, because Paper caps the combat tracker itself there. On 1.21.11 it doesn't. Checked directly in this branch's CombatTracker.java: the field falls back to a plain unbounded Lists.newArrayList(), recordDamageAndCheckCombatState does a bare entries.add(...), and maxTrackingCombatEntries appears nowhere in the file.

So at the stock default, a mob taking sustained damage — lava, cactus, drowning, fire — accumulates combat entries forever. That's MC-301114, live and unmitigated. This build bounds it.

Also enabled

• cache-biome — caches biome lookups on the paths that hit them repeatedly every tick. Verified wired in LocationPredicate and four NaturalSpawner call sites in this tree.
• Virtual threads for two more background pools (bukkit-async-scheduler, download-pool). This branch already ships two others on by default.

Deliberately left off

fast-biome-manager-seed-obfuscation — exists on this track but not 26.2, so it got a fresh look. It swaps BiomeManager's SHA-256 seed obfuscation for XXHash, and that seed drives biome edge fuzzing, so it would shift biome boundaries. Worldgen change, not free speed.

Everything else still off is documented with its reason in 1.21.11/NOTES.md.

Verified

Booted with the full tuned config: clean load, no exceptions, brand string correct, config renames working, every changed setting survived the server rewriting the config byte-identical, clean shutdown.

Downloads

• AtlasSpigot-1.21.11.jar — the server
• AtlasSpigot-1.21.11-config.zip — the tuned config, ready to drop in alongside it

Set eula=true before first boot.