- Migrate connection pool from manual LinkedBlockingQueue to HikariCP
(eliminates isValid() ping on every query visible in Spark profiler)
- Move ALL DB writes off server thread: logout uses snapshot+async+latch,
shutdown uses snapshot+CompletableFuture.allOf for parallel saves
- Pre-read curios/accessories/cosmeticarmor/attachments on background
thread during login (4-7 fewer DB queries on main thread per login)
- Auto-save interval increased to 5 minutes
- Fix pool shutdown ordering: shutdownPool() now runs AFTER all shutdown
saves complete (previously could fire before, silently losing all data)
- Fix connection leak in executeQuery/executePreparedQuery when
prepareStatement throws (leaked connections exhaust HikariCP pool)
- Fix duplication bug: saveStorageContents guard used nbt.size()<=1 which
blocked legitimately emptied backpacks from saving to DB
- Fix stale SaveToFile overwriting logout: check playerLocks.containsKey
before writing to prevent stale background task from regressing data
- Remove LIMIT 1000 on startup online=0 reset (could leave players stuck)
- Add executorService.shutdown() on server stop to prevent JVM hang
- Add apply methods (applyCuriosFromData, applyAccessoriesFromData, etc.)
to separate entity writes from DB reads for thread-safe restore
- Add UUID collectors (collectBackpackUuids, collectSSUuids) and
background save methods for snapshot+async logout/shutdown pattern
Spark showed PlayerSync consuming 10.16% of the server thread, almost
entirely from DriverManager.getConnection() (TCP handshake + MySQL auth
+ USE db) called for EVERY single query. With auto-save every 60s,
each player generated ~6 new connections per save cycle on main thread.
FIX: Simple connection pool (LinkedBlockingQueue, 5 connections).
- Connections are reused instead of opened/closed per query
- isValid(2) check before reuse to detect dead connections
- returnConnection() puts connections back in pool instead of closing
- QueryResult.close() also returns to pool
- autoReconnect=true in JDBC URL for resilience
- shutdownPool() for clean server stop
- Non-database connections (startup DDL) bypass the pool
Expected improvement: ~90% reduction in MySQL overhead on server thread.
Vyrriox
CRITICAL-1/2: Remove duplicate online=1 writes from doPlayerJoin.
The synchronous onPlayerLoggedInKickCheck already sets online=1.
The background thread writes raced with logout's online=0, permanently
locking players as "online" after crash-disconnect during join.
HIGH-1: Startup SQL uses PreparedStatement for server_id (was string concat).
HIGH-2: update() method now uses try-with-resources for PreparedStatement.
HIGH-3: NPE guard in RS2 data file logging when getRS2DataFile returns null.
Vyrriox
- Fix advancements disappearing: use PreparedStatements for all SQL with
user data (advancement JSON contains chars that broke string-concat SQL),
add null safety for advancement file
- Fix multi-server kick: run doPlayerConnect synchronously instead of async
(players could join before the duplicate check completed)
- Fix Curios disappearing: clear slots AFTER validating data exists (not
before), use CuriosCache for dead players on logout instead of empty API
- Fix Sophisticated Storage items: add storeSophisticatedStorageItems() and
restoreSophisticatedStorageItems() to sync packed barrels/shulkers/chests
- Anti-duplication: clear all inventories before restoring from DB on join
- Fix tick counter: remove LevelTickEvent (fired per dimension = 3x too
fast), merge heartbeat into ServerTickEvent
- Fix connection leaks: use try-with-resources for all QueryResult
- Fix logout order: save data BEFORE marking player offline
- Skip auto-save for dead/unsynced players to prevent saving empty data
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
