chore(deploy): tune postgres memory parameters and limit (CACHE-2)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docker-compose.yml

@@ -19,6 +19,27 @@ services:
   postgres:
     image: postgres:16-alpine
     restart: unless-stopped
+    # 内存参数按 4C/8G 机器给 PG 3G 设定(CACHE-2);机器不同按 docs/runbook/storage.md「PG 参数」调整,
+    # 改 .env 里的 PG_* 后 docker compose up -d postgres 重建生效
+    command:
+      - postgres
+      - -c
+      - shared_buffers=${PG_SHARED_BUFFERS:-2GB}
+      - -c
+      - effective_cache_size=${PG_EFFECTIVE_CACHE_SIZE:-5GB}
+      - -c
+      - work_mem=${PG_WORK_MEM:-32MB}
+      - -c
+      - maintenance_work_mem=${PG_MAINTENANCE_WORK_MEM:-256MB}
+      - -c
+      - max_wal_size=${PG_MAX_WAL_SIZE:-2GB}
+    mem_limit: ${PG_MEM_LIMIT:-3g}
+    deploy:
+      resources:
+        limits:
+          memory: ${PG_MEM_LIMIT:-3g}
+    # 并行查询的动态共享内存走 /dev/shm,Docker 缺省 64MB 不够
+    shm_size: 512mb
     environment:
       POSTGRES_USER: umt
       POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?请设置 POSTGRES_PASSWORD}