Tune SQLite caches and maintain planner statistics

src/lib/server/db/connection.ts

@@ -0,0 +1,12 @@
+import type Database from 'better-sqlite3';
+
+export function tuneConnection(handle: Database.Database, reader = false): void {
+    handle.pragma(`cache_size = -${reader ? 32768 : 131072}`);
+    handle.pragma('temp_store = MEMORY');
+    // mmap is opt-in because the controller data directory can be a network mount.
+    const mmapMiB = Number(process.env.EC_SQLITE_MMAP_MB ?? 0);
+    if (Number.isSafeInteger(mmapMiB) && mmapMiB >= 0 && mmapMiB <= 32768) {
+        handle.pragma(`mmap_size = ${mmapMiB * 1024 * 1024}`);
+    }
+    if (!reader) handle.pragma('journal_size_limit = 67108864');
+}

src/lib/server/db/index.ts

@@ -12,9 +12,11 @@ import { migrateServerHistory } from './server-history.js';
 import { migrateNativeInstances } from '../backends/schema.js';
 import { installPerformanceIndexes } from './performance-indexes.js';
 import { migrateVersionLayout } from './version-layout.js';
+import { tuneConnection } from './connection.js';
 import { timeStatement } from './slow-statements.js';
 
 let _db: Database.Database | null = null;
+let optimizeTimer: NodeJS.Timeout | undefined;
 
 // Desired shape of the `servers` table. Every column here is added to the
 // table on boot if missing — introspection via PRAGMA table_info handles
@@ -316,6 +318,7 @@ export function db(): Database.Database {
     try {
         handle.pragma('journal_mode = WAL');
         handle.pragma('foreign_keys = ON');
+        tuneConnection(handle);
         dropLegacyBetaTables(handle);
         handle.exec(schemaSql);
         migrateProvisioningActions(handle);
@@ -409,6 +412,7 @@ export function db(): Database.Database {
             ON server_deployments(id) WHERE state NOT IN ('done','warning','cancelled');`);
         installPerformanceIndexes(handle);
         installReportRevisions(handle);
+        handle.pragma('optimize = 0x10002');
     } catch (err) {
         handle.close();
         throw err;
@@ -431,10 +435,17 @@ export function db(): Database.Database {
     }) as typeof handle.prepare;
 
     _db = handle;
+    optimizeTimer = setInterval(() => {
+        try { handle.pragma('optimize'); }
+        catch (error) { console.error('[database] optimize failed:', error); }
+    }, 60 * 60_000);
+    optimizeTimer.unref();
     return _db;
 }
 
 export function closeDb(): void {
+    clearInterval(optimizeTimer);
+    optimizeTimer = undefined;
     if (_db) {
         _db.close();
         _db = null;

src/lib/server/reports/database.ts

@@ -1,5 +1,7 @@
 import Database from 'better-sqlite3';
 import { workerData } from 'node:worker_threads';
+import { tuneConnection } from '../db/connection.js';
 
 const handle = new Database(workerData.dbPath, { readonly: true, fileMustExist: true });
+tuneConnection(handle, true);
 export function db() { return handle; }