diff --git a/apps/server/src/modules/auth-settings/provided.ts b/apps/server/src/modules/auth-settings/provided.ts
index 743c407c..430be9d9 100644
--- a/apps/server/src/modules/auth-settings/provided.ts
+++ b/apps/server/src/modules/auth-settings/provided.ts
@@ -1,5 +1,11 @@
 import { createCipheriv, createDecipheriv, createHmac, randomBytes, randomUUID } from "node:crypto";
-import { DEFAULT_SETTINGS, GlobalSettings, type SecretPurpose, type SettingsKey } from "@umt/contracts";
+import {
+  DEFAULT_SETTINGS,
+  GlobalSettings,
+  type SecretPurpose,
+  type SettingsKey,
+  withStorageDefaults,
+} from "@umt/contracts";
 import type { DB, Kysely } from "@umt/db";
 import type { Logger } from "pino";
 import type { EventBusPort } from "../../http/sse.ts";
@@ -335,7 +341,13 @@ export function createSettingsReader(deps: {
     for (const key of Object.keys(DEFAULT_SETTINGS) as SettingsKey[]) {
       const def = DEFAULT_SETTINGS[key];
       const v = stored.get(key);
-      const merged = v && typeof v === "object" && !Array.isArray(v) ? { ...def, ...(v as object) } : def;
+      // storage 是两层结构:逐层补缺省,旧库里缺子字段也能整体通过校验
+      const merged =
+        key === "storage"
+          ? withStorageDefaults(v)
+          : v && typeof v === "object" && !Array.isArray(v)
+            ? { ...def, ...(v as object) }
+            : def;
       const parsed = GlobalSettings.shape[key].safeParse(merged);
       if (!parsed.success) deps.logger.warn({ key }, "settings 值不合法，回退缺省");
       out[key] = parsed.success ? parsed.data : def;
diff --git a/packages/contracts/src/settings.ts b/packages/contracts/src/settings.ts
index 4b459a7b..ff40acbd 100644
--- a/packages/contracts/src/settings.ts
+++ b/packages/contracts/src/settings.ts
@@ -24,11 +24,14 @@ const CacheShape = z.object({
   checkIntervalSec: z.number().int().min(10).max(3600),
   /** 缓存清理的目标使用率(低水位) */
   cleanupTargetPercent: Percent,
-  /** TMDB 缓存(请求响应 + 识别结果)保留小时数(对照 MP META_CACHE_EXPIRE,缺省 24) */
+  /**
+   * @deprecated CACHE-2 起由 storage.cacheTtl(tmdbSearchDays / tmdbDetailDays)取代,服务端不再读取;
+   * 保留在 schema 里只为兼容已存的 JSON 与旧设置页。
+   */
   tmdbTtlHours: z.number().int().min(1).max(720),
   /** TMDB 缓存每类条数上限,超出删最旧(对照 MP CONF.tmdb,缺省 256;大内存模式 1024) */
   tmdbMaxSize: z.number().int().min(16).max(100_000),
-  /** 空结果 / 未识别的短缓存秒数(对照 MP EMPTY_RESULT_CACHE_TTL,缺省 1800) */
+  /** @deprecated CACHE-2 起由 storage.cacheTtl.tmdbMissDays 取代,服务端不再读取 */
   emptyResultTtlSec: z.number().int().min(0).max(86_400),
   /** 图片代理落盘缓存(对照 MP GLOBAL_IMAGE_CACHE,缺省关闭;关闭时仍代理,只是不落盘) */
   globalImageCache: z.boolean(),
@@ -410,7 +413,7 @@ export const DEFAULT_ENRICH_DOMAINS: string[] = [
 
 export const IdentitySettings = z.object({
   eagerTmdbLookup: z.boolean(),
-  /** 待识别池里 unmatched 条目多少天没有新证据就归档(仍可按状态筛出、可手动指定) */
+  /** @deprecated CACHE-2 起由 storage.retentionDays.identityPoolArchive 取代,服务端不再读取 */
   poolArchiveDays: z.number().int().min(1).max(3650),
   /**
    * META-1:订阅别名 / 新作品收录规则命中、TMDB 却查不到时自动尝试一次元数据补全(只出建议,不建作品)。
@@ -432,6 +435,98 @@ export const IdentitySettings = z.object({
 });
 export type IdentitySettings = z.infer<typeof IdentitySettings>;
 
+// ── 存储预算与保留(CACHE-2,docs/runbook/storage.md)──
+
+const Gb = z.number().min(0.01).max(10_000);
+const Days = z.number().int().min(1).max(3650);
+
+export const StorageBudgets = z
+  .object({
+    /** PG 数据目录预算(GB):超过 pgDataWarnGb 告警,超过本值 critical */
+    pgDataGb: Gb,
+    pgDataWarnGb: Gb,
+    /** 图片代理缓存容量(GB):超出按最久未访问删除(LRU) */
+    imagesGb: Gb,
+    /** DATA_DIR/backups 占用预算(GB) */
+    backupsGb: Gb,
+    /** Agent 会话 + 视觉证据(DATA_DIR/agent-sessions、tmp/evidence)预算(GB) */
+    sessionsEvidenceGb: Gb,
+  })
+  .refine((v) => v.pgDataWarnGb <= v.pgDataGb, { message: "PG 告警线不得高于预算" });
+export type StorageBudgets = z.infer<typeof StorageBudgets>;
+
+/** 各类流水数据保留期(到期由 storage.retention.* 定时任务分批删除) */
+export const StorageRetentionDays = z.object({
+  /** observation(Feed 观察) */
+  observation: Days,
+  /** sse_event(SSE 补读) */
+  sseEvent: Days,
+  /** process_heartbeat_sample(小时) */
+  heartbeatHours: z
+    .number()
+    .int()
+    .min(1)
+    .max(24 * 90),
+  /** 已结束的业务任务 task 与引擎 run */
+  taskRun: Days,
+  /** 已结束 Agent 会话的 agent_run_event / agent_run_message */
+  agentEvent: Days,
+  /** audit_event(能力调用审计除外) */
+  audit: Days,
+  /** 能力调用统计:audit_event(target_type=capability)与已结束的 capability_invocation */
+  capabilityStats: Days,
+  /** 待识别池 unmatched 条目无新证据多少天后归档 */
+  identityPoolArchive: Days,
+});
+export type StorageRetentionDays = z.infer<typeof StorageRetentionDays>;
+
+/** 缓存有效期(天):只改 TTL 的取值来源,缓存语义仍对照 MP(docs/porting/moviepilot-tmdb-cache.md) */
+export const StorageCacheTtl = z.object({
+  /** TMDB 搜索 / find 响应与识别结果 */
+  tmdbSearchDays: Days,
+  /** TMDB 详情(/movie/{id}、/tv/{id}、季);追踪中的作品命中时续期 */
+  tmdbDetailDays: Days,
+  /** TMDB 空结果与未识别负缓存(MP EMPTY_RESULT_CACHE_TTL) */
+  tmdbMissDays: Days,
+  /** 站点详情页扩展内容(kv_cache site.detail) */
+  siteDetailDays: Days,
+  /** 网页搜索结果 */
+  webSearchDays: Days,
+});
+export type StorageCacheTtl = z.infer<typeof StorageCacheTtl>;
+
+export const StorageSettings = z.object({
+  budgets: StorageBudgets,
+  retentionDays: StorageRetentionDays,
+  cacheTtl: StorageCacheTtl,
+});
+export type StorageSettings = z.infer<typeof StorageSettings>;
+
+export const DEFAULT_STORAGE_SETTINGS: StorageSettings = {
+  budgets: { pgDataGb: 25, pgDataWarnGb: 20, imagesGb: 20, backupsGb: 20, sessionsEvidenceGb: 10 },
+  retentionDays: {
+    observation: 90,
+    sseEvent: 7,
+    heartbeatHours: 24,
+    taskRun: 60,
+    agentEvent: 90,
+    audit: 180,
+    capabilityStats: 90,
+    identityPoolArchive: 30,
+  },
+  cacheTtl: { tmdbSearchDays: 7, tmdbDetailDays: 30, tmdbMissDays: 1, siteDetailDays: 7, webSearchDays: 1 },
+};
+
+/** 存储设置与缺省逐层合并(旧库里缺子字段时补齐) */
+export function withStorageDefaults(v: unknown): StorageSettings {
+  const o = (v && typeof v === "object" ? v : {}) as Partial<Record<keyof StorageSettings, object>>;
+  return {
+    budgets: { ...DEFAULT_STORAGE_SETTINGS.budgets, ...(o.budgets ?? {}) },
+    retentionDays: { ...DEFAULT_STORAGE_SETTINGS.retentionDays, ...(o.retentionDays ?? {}) },
+    cacheTtl: { ...DEFAULT_STORAGE_SETTINGS.cacheTtl, ...(o.cacheTtl ?? {}) },
+  } as StorageSettings;
+}
+
 export const GlobalSettings = z.object({
   automation: AutomationSettings,
   cache: CacheSettings,
@@ -445,6 +540,7 @@ export const GlobalSettings = z.object({
   naming: NamingSettings,
   identity: IdentitySettings,
   search: SearchSettings,
+  storage: StorageSettings,
 });
 export type GlobalSettings = z.infer<typeof GlobalSettings>;
 
@@ -526,6 +622,7 @@ export const DEFAULT_SETTINGS: GlobalSettings = {
     enrichDomains: DEFAULT_ENRICH_DOMAINS,
   },
   search: { defaultSiteMode: "default", siteIds: [] },
+  storage: DEFAULT_STORAGE_SETTINGS,
 };
 
 /** PATCH /settings:按分组部分更新;服务端与现值合并后用 GlobalSettings 整体再校验 */
@@ -576,6 +673,13 @@ export const GlobalSettingsUpdate = z.object({
   naming: NamingSettings.partial().optional(),
   identity: IdentitySettings.partial().optional(),
   search: SearchSettings.partial().optional(),
+  storage: z
+    .object({
+      budgets: z.object(StorageBudgets.shape).partial().optional(),
+      retentionDays: StorageRetentionDays.partial().optional(),
+      cacheTtl: StorageCacheTtl.partial().optional(),
+    })
+    .optional(),
 });
 export type GlobalSettingsUpdate = z.infer<typeof GlobalSettingsUpdate>;
 
@@ -602,6 +706,16 @@ export function mergeSettings(current: GlobalSettings, patch: GlobalSettingsUpda
     naming: { ...(current.naming ?? DEFAULT_SETTINGS.naming), ...patch.naming },
     identity: { ...(current.identity ?? DEFAULT_SETTINGS.identity), ...patch.identity },
     search: { ...(current.search ?? DEFAULT_SETTINGS.search), ...patch.search },
+    storage: mergeStorage(current.storage, patch.storage),
+  };
+}
+
+function mergeStorage(current: StorageSettings | undefined, patch: GlobalSettingsUpdate["storage"]): StorageSettings {
+  const base = withStorageDefaults(current);
+  return {
+    budgets: { ...base.budgets, ...patch?.budgets },
+    retentionDays: { ...base.retentionDays, ...patch?.retentionDays },
+    cacheTtl: { ...base.cacheTtl, ...patch?.cacheTtl },
   };
 }
 
@@ -638,6 +752,10 @@ export const DEPRECATED_SETTINGS_FIELDS = [
   "pi.model",
   "pi.thinkingLevel",
   "pi.apiKeySecretRef",
+  // CACHE-2:由 storage.cacheTtl / storage.retentionDays 取代
+  "cache.tmdbTtlHours",
+  "cache.emptyResultTtlSec",
+  "identity.poolArchiveDays",
 ] as const;
 
 // ── 设置页分区(docs/design/console-ia.md §3.4) ──
@@ -682,6 +800,7 @@ export const SETTINGS_SECTIONS: readonly SettingsSectionDef[] = [
       { id: "cache", label: "缓存水位" },
       { id: "budget", label: "每日预算" },
       { id: "retention", label: "保留" },
+      { id: "storage", label: "存储与保留" },
     ],
     fields: [
       "automation.enabled",
@@ -695,6 +814,9 @@ export const SETTINGS_SECTIONS: readonly SettingsSectionDef[] = [
       "budget.maxConcurrentDownloads",
       "retention.seedRetentionDays",
       "retention.logRetentionDays",
+      "storage.budgets",
+      "storage.retentionDays",
+      "storage.cacheTtl",
     ],
     resources: [],
   },
@@ -774,11 +896,8 @@ export const SETTINGS_SECTIONS: readonly SettingsSectionDef[] = [
     fields: [
       "metadata.tmdbApiKeySecretRef",
       "metadata.tmdbBaseUrl",
-      "cache.tmdbTtlHours",
       "cache.tmdbMaxSize",
-      "cache.emptyResultTtlSec",
       "identity.eagerTmdbLookup",
-      "identity.poolArchiveDays",
       "identity.autoEnrich",
       "identity.enrichDailyBudget",
       "identity.enrichDomains",