diff --git a/server/routes.ts b/server/routes.ts
index 778891c..4496682 100644
--- a/server/routes.ts
+++ b/server/routes.ts
@@ -16,6 +16,12 @@ import { tokenFromRequest, tokenMatches } from './auth.ts'
 import type { ConfigObject } from '../vendor/config-editor/index.ts'
 import type { Env } from './env.ts'
 
+/**
+ * 延迟测试。名字里可能有斜杠和中文，所以按前缀匹配而不是列进上面那个精确白名单。
+ * 它是 GET 但会真的发起网络连接，属于「读」里比较重的一类，单独列出来提醒这一点。
+ */
+const DELAY_PATH = /^\/(proxies|group)\/.+\/delay$/
+
 /** 允许透传的管理接口路径。白名单而不是黑名单——多开一个口子要有意为之。 */
 const READABLE_KERNEL_PATHS = new Set([
   '/version',
@@ -118,7 +124,7 @@ export function createRouter(env: Env, token: string) {
 
     if (path.startsWith('/api/kernel/') && req.method === 'GET') {
       const target = path.slice('/api/kernel'.length)
-      if (!READABLE_KERNEL_PATHS.has(target)) {
+      if (!READABLE_KERNEL_PATHS.has(target) && !DELAY_PATH.test(target)) {
         return json({ error: `不允许透传这个路径：${target}` }, 403)
       }
       const upstream = await proxyGet(env, target + url.search)
diff --git a/web/App.vue b/web/App.vue
index 7a61cc5..11c561f 100644
--- a/web/App.vue
+++ b/web/App.vue
@@ -15,11 +15,19 @@ const providerLines = ref<string[]>([])
 const runtime = ref<Record<string, ProxyInfo>>({})
 const needsToken = ref(!getToken())
 const loadError = ref('')
-const loading = ref(false)
+const booted = ref(false)
+const refreshing = ref(false)
 const active = ref('router')
 
+/**
+ * 重新读一遍状态。
+ *
+ * 关键在于**不能把页面拆掉重建**：之前每次刷新都会先切到「读取中」，
+ * 于是路由页被卸载、选中的那一路入站丢失，改完一个设置还要重新找回原来的位置。
+ * 所以只有首次加载显示占位，之后都是原地更新。
+ */
 async function load() {
-  loading.value = true
+  refreshing.value = true
   loadError.value = ''
   try {
     const [config, status] = await Promise.all([api.readConfig(), api.kernel()])
@@ -37,7 +45,8 @@ async function load() {
       loadError.value = error instanceof Error ? error.message : String(error)
     }
   } finally {
-    loading.value = false
+    refreshing.value = false
+    booted.value = true
   }
 }
 
@@ -62,6 +71,17 @@ async function readRuntime(): Promise<Record<string, ProxyInfo>> {
   }
 }
 
+/**
+ * 切换策略组时先在本地改掉，不等内核回话。
+ *
+ * 这一步不写配置文件，失败率极低；而等一个往返再更新会让点击感觉发木。
+ * 真失败了随后的刷新会把状态纠正回来。
+ */
+function optimisticSelect(group: string, member: string) {
+  const info = runtime.value[group]
+  if (info) info.now = member
+}
+
 function submitToken(value: string) {
   setToken(value)
   void load()
@@ -119,7 +139,7 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
     </nav>
 
     <main class="main">
-      <p v-if="loading" class="note">读取中</p>
+      <p v-if="!booted && refreshing" class="note">读取中</p>
 
       <div v-else-if="loadError" class="alert">
         <h2>读不到配置</h2>
@@ -144,6 +164,7 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
           :provider-lines="providerLines"
           :runtime="runtime"
           @changed="load"
+          @optimistic-select="optimisticSelect"
         />
 
         <div v-else class="note">
diff --git a/web/api.ts b/web/api.ts
index 3bd852a..0ddc688 100644
--- a/web/api.ts
+++ b/web/api.ts
@@ -8,6 +8,9 @@ import type { ConfigDiagnostic, ConfigObject } from '../vendor/config-editor/ind
 
 const TOKEN_KEY = 'patchbay.token'
 
+/** 测延迟用的目标。204 空响应，体积最小，全球都有部署。 */
+const TEST_URL = 'https://www.gstatic.com/generate_204'
+
 export function getToken(): string {
   return localStorage.getItem(TOKEN_KEY) ?? ''
 }
@@ -134,6 +137,20 @@ export const api = {
       name: member,
     }),
 
+  /** 测一条线路的延迟。返回的是这一次的结果，同时也会被记进内核的历史里。 */
+  testLine: (name: string, url = TEST_URL, timeout = 5000) =>
+    request<{ delay: number }>(
+      'GET',
+      `/api/kernel/proxies/${encodeURIComponent(name)}/delay?url=${encodeURIComponent(url)}&timeout=${String(timeout)}`,
+    ),
+
+  /** 测一整个策略组，内核会并发测所有成员。返回每个成员的延迟。 */
+  testGroup: (group: string, url = TEST_URL, timeout = 5000) =>
+    request<Record<string, number>>(
+      'GET',
+      `/api/kernel/group/${encodeURIComponent(group)}/delay?url=${encodeURIComponent(url)}&timeout=${String(timeout)}`,
+    ),
+
   /** 订阅里当前有哪些线路。配置文件给不出这个答案，只能问运行中的内核。 */
   providers: () =>
     request<{ providers: Record<string, { vehicleType: string; proxies: { name: string }[] }> }>(
diff --git a/web/views/InboundDetail.vue b/web/views/InboundDetail.vue
index 24182e6..72e4194 100644
--- a/web/views/InboundDetail.vue
+++ b/web/views/InboundDetail.vue
@@ -6,7 +6,7 @@ import type { ProxyInfo } from '../api'
 import IconOffline from '~icons/ri/cloud-off-line'
 import IconEdit from '~icons/ri/edit-line'
 import IconDelete from '~icons/ri/delete-bin-line'
-import IconConvert from '~icons/ri/swap-line'
+import IconFlash from '~icons/ri/flashlight-line'
 
 const props = defineProps<{
   inbound: Inbound
@@ -19,14 +19,16 @@ const props = defineProps<{
   runtime: Record<string, ProxyInfo>
   kernelOnline: boolean
   saving: boolean
+  /** 正在测延迟 */
+  testing: boolean
 }>()
 
 const emit = defineEmits<{
   pick: [mode: OutboundMode]
   edit: []
   remove: []
-  convert: []
   select: [group: string, member: string]
+  test: [group: string]
 }>()
 
 /**
@@ -175,7 +177,18 @@ function delayClass(ms: number | null): string {
       </p>
 
       <template v-if="switchable">
-        <h4>{{ switchable.group }} 当前选中</h4>
+        <div class="sub-head">
+          <h4>{{ switchable.group }} 当前选中</h4>
+          <button
+            type="button"
+            class="flash"
+            :disabled="testing"
+            :title="`测试 ${switchable.group} 里所有线路的延迟`"
+            @click="emit('test', switchable.group)"
+          >
+            <IconFlash />
+          </button>
+        </div>
         <div class="grid">
           <button
             v-for="m in switchable.members"
@@ -198,15 +211,9 @@ function delayClass(ms: number | null): string {
     <section class="pick">
       <h3>出站</h3>
 
-      <div v-if="locked" class="convert">
-        <p>
-          由 <code>{{ inbound.legacyKey }}</code> 声明，这种写法没有 proxy 字段，出站固定是
-          <span class="mono">RULE</span>，下面这些都不能选。
-        </p>
-        <button type="button" :disabled="saving" @click="emit('convert')">
-          <IconConvert /> 转成命名入站
-        </button>
-      </div>
+      <p v-if="locked" class="aside-note">
+        由 <code>{{ inbound.legacyKey }}</code> 声明，这种写法没有 proxy 字段，出站固定是 RULE
+      </p>
 
       <div v-if="!locked" class="grid">
         <button
@@ -373,43 +380,37 @@ function delayClass(ms: number | null): string {
   cursor: not-allowed;
 }
 
-.convert {
-  display: flex;
-  flex-direction: column;
-  align-items: flex-start;
-  gap: var(--s-3);
-  padding: var(--s-3);
-  border: 1px solid var(--c-border);
-  border-radius: var(--r-sm);
-  background: var(--c-surface-sunken);
-  margin-bottom: var(--s-4);
+.is-dim {
+  opacity: 0.6;
 }
 
-.convert p {
-  color: var(--c-text-soft);
-  font-size: var(--t-sm);
-  line-height: 1.6;
-}
-
-.convert button {
+.sub-head {
   display: flex;
   align-items: center;
+  justify-content: space-between;
   gap: var(--s-2);
-  padding: var(--s-2) var(--s-3);
-  border: 1px solid var(--c-border-strong);
+}
+
+.flash {
+  display: grid;
+  place-items: center;
+  width: 26px;
+  height: 26px;
+  border: 1px solid transparent;
   border-radius: var(--r-sm);
-  background: var(--c-surface);
-  font-size: var(--t-sm);
+  background: none;
+  color: var(--c-text-faint);
   cursor: pointer;
 }
 
-.convert button:hover:not(:disabled) {
-  border-color: var(--c-accent);
+.flash:hover:not(:disabled) {
+  background: var(--c-accent-soft);
   color: var(--c-accent-text);
 }
 
-.is-dim {
-  opacity: 0.6;
+.flash:disabled {
+  cursor: progress;
+  opacity: 0.5;
 }
 
 .pick {
diff --git a/web/views/RouterPage.vue b/web/views/RouterPage.vue
index c8b1fc1..b4372d1 100644
--- a/web/views/RouterPage.vue
+++ b/web/views/RouterPage.vue
@@ -23,7 +23,7 @@ const props = defineProps<{
   runtime: Record<string, ProxyInfo>
 }>()
 
-const emit = defineEmits<{ changed: [] }>()
+const emit = defineEmits<{ changed: []; optimisticSelect: [group: string, member: string] }>()
 
 const inbounds = computed(() => collectInbounds(props.data))
 const outbounds = computed(() => collectOutboundNames(props.data))
@@ -35,8 +35,7 @@ const done = ref('')
 const fields = ref<ListenerFields | null>(null)
 const formOpen = ref(false)
 const formEditing = ref<Inbound | null>(null)
-/** 正在把哪个老式端口字段转成命名入站。null 表示不是在做转换 */
-const convertingKey = ref<string | null>(null)
+const testing = ref(false)
 
 onMounted(async () => {
   try {
@@ -116,30 +115,13 @@ async function pickOutbound(mode: OutboundMode) {
 
 function openAdd() {
   formEditing.value = null
-  convertingKey.value = null
   formOpen.value = true
 }
 
-/**
- * 把一个老式顶层端口转成命名入站。
- *
- * 转完它才有 proxy 字段，才能单独指定出站。表单预填端口、类型和它当前实际绑定的地址
- * （老式端口的地址是内核从 allow-lan 和 bind-address 推出来的，转换后要显式写进 listen，
- * 否则改 allow-lan 会连带影响这个端口）。名字留空，让用户自己起一个——沿用 mixed-port
- * 当名字很难看。
- */
-function openConvert() {
-  const target = selected.value
-  if (!target?.legacyKey) return
-  formEditing.value = { ...target, name: '' }
-  convertingKey.value = target.legacyKey
-  formOpen.value = true
-}
 
 function openEdit() {
   if (!selected.value || selected.value.isDefault) return
   formEditing.value = selected.value
-  convertingKey.value = null
   formOpen.value = true
 }
 
@@ -147,41 +129,50 @@ async function submitForm(entry: ConfigObject) {
   const next = clone()
   const listeners = Array.isArray(next.listeners) ? (next.listeners as ConfigObject[]) : []
   const editingIndex = formEditing.value?.listenerIndex ?? null
-  const converting = convertingKey.value
 
   if (editingIndex === null) listeners.push(entry)
   else listeners[editingIndex] = entry
   next.listeners = listeners
 
-  // 转换时把老式端口字段去掉，否则同一个端口会被声明两次，内核起不来
-  if (converting) delete next[converting]
-
   formOpen.value = false
-  convertingKey.value = null
-  const what = converting
-    ? `${converting} 转成了命名入站 ${String(entry.name)}`
-    : editingIndex === null
-      ? `新增了 ${String(entry.name)}`
-      : '改动已保存'
-  await commit(next, what)
+  await commit(next, editingIndex === null ? `新增了 ${String(entry.name)}` : '改动已保存')
   if (editingIndex === null) selectedId.value = `listener:${String(listeners.length - 1)}`
 }
 
 /** 切换策略组当前选中谁。运行时动作，不写配置文件，所以不走那条落盘链路。 */
 async function selectMember(group: string, member: string) {
   if (saving.value) return
-  saving.value = true
+  // 先本地改掉，别让点击等一个往返。失败了随后的刷新会纠正回来。
+  emit('optimisticSelect', group, member)
   failure.value = null
   done.value = ''
   try {
     await api.selectProxy(group, member)
-    done.value = `${group} 切到了 ${member}`
     emit('changed')
   } catch (error) {
     const message = error instanceof ApiError ? String(error.payload.error ?? error.message) : String(error)
     failure.value = { message, hint: '这一步只改内核的运行状态，配置文件没有被动过。' }
+  }
+}
+
+/** 让内核并发测一个策略组里所有成员的延迟，测完刷新一次拿到新数字。 */
+async function testGroup(group: string) {
+  if (testing.value) return
+  testing.value = true
+  failure.value = null
+  done.value = ''
+  try {
+    const result = await api.testGroup(group)
+    const ok = Object.values(result).filter((ms) => ms > 0).length
+    done.value = `${group} 测完了，${ok} / ${Object.keys(result).length} 条通`
+    emit('changed')
+  } catch (error) {
+    // 测不通是关于线路的结论，不是 Patchbay 出了问题，所以用中性提示而不是错误框。
+    // 内核在全部超时时回 504，单条测失败回 503，两种都属于「测出来了，结果不好」。
+    const raw = error instanceof ApiError ? String(error.payload.message ?? error.message) : String(error)
+    done.value = raw.includes('timeout') ? `${group} 里的线路全部超时` : `测试没能完成：${raw}`
   } finally {
-    saving.value = false
+    testing.value = false
   }
 }
 
@@ -265,8 +256,9 @@ async function removeSelected() {
         @pick="pickOutbound"
         @edit="openEdit"
         @remove="removeSelected"
-        @convert="openConvert"
         @select="selectMember"
+        @test="testGroup"
+        :testing="testing"
       />
     </div>