perf(ui): index and batch session updates

Batch global session, status, ordering, and activity timing mutations at the existing directory event boundary so large subagent bursts publish each owner once.

Maintain active session roots, children, and directory buckets in the global store, reuse them in Sidebar projections, and avoid rebuilding live aggregates and structural data for unrelated renders while preserving authoritative ordering reconciliation.

packages/ui/src/sync/session-event-router.ts

@@ -1,5 +1,10 @@
 import type { Event, Session } from "@opencode-ai/sdk/v2/client"
-import { isGlobalSessionRecencyOnlyUpdate, useGlobalSessionsStore } from "@/stores/useGlobalSessionsStore"
+import {
+  isGlobalSessionRecencyOnlyUpdate,
+  mergeSessionDirectoryMetadata,
+  useGlobalSessionsStore,
+  type GlobalSessionMutation,
+} from "@/stores/useGlobalSessionsStore"
 import { getRuntimeKey, subscribeRuntimeEndpointWillChange } from "@/lib/runtime-switch"
 import { streamPerfCount, streamPerfMark } from "@/stores/utils/streamDebug"
 import { stripSessionDiffSnapshots } from "./sanitize"
@@ -11,23 +16,6 @@ const clearPendingGlobalSessionUpdates = (): void => {
   pendingGlobalSessionUpdates.clear()
 }
 
-const flushPendingGlobalSessionUpdate = (sessionID: string): void => {
-  const update = pendingGlobalSessionUpdates.get(sessionID)
-  pendingGlobalSessionUpdates.delete(sessionID)
-  if (!update) return
-  const runtimeKey = getRuntimeKey()
-  if (update.runtimeKey !== runtimeKey) return
-  const currentSession = getGlobalSessionSnapshot(update.session.id)
-  if (
-    !currentSession
-    || shouldSkipStaleSessionEvent(currentSession, update.session)
-    || !isGlobalSessionRecencyOnlyUpdate(currentSession, update.session)
-  ) return
-  streamPerfMark("global_sessions.event_update_flush")
-  useGlobalSessionsStore.getState().upsertSession(update.session)
-  streamPerfCount("ui.global_sessions.event_update_publication")
-}
-
 const scheduleGlobalSessionUpdate = (session: Session): void => {
   pendingGlobalSessionUpdates.set(session.id, { runtimeKey: getRuntimeKey(), session })
   streamPerfCount("ui.global_sessions.event_update_deferred")
@@ -58,51 +46,82 @@ const getSessionInfoFromPayload = (event: Event): Session | null => {
   return stripSessionDiffSnapshots(session as Session)
 }
 
-const getGlobalSessionSnapshot = (sessionId: string): Session | null => {
-  const global = useGlobalSessionsStore.getState()
-  return [...global.activeSessions, ...global.archivedSessions].find((session) => session.id === sessionId) ?? null
+export const applySessionEventsToGlobalSessions = (payloads: readonly Event[]): void => {
+  if (payloads.length === 0) return
+  const runtimeKey = getRuntimeKey()
+  const store = useGlobalSessionsStore.getState()
+  const overlay = new Map(store.entityById)
+  const mutations: GlobalSessionMutation[] = []
+  let flushedRecency = false
+
+  const appendUpsert = (session: Session): void => {
+    const existing = overlay.get(session.id) ?? null
+    const merged = mergeSessionDirectoryMetadata(session, existing)
+    overlay.set(session.id, merged)
+    mutations.push({ type: "upsert", session: merged })
+  }
+
+  for (const payload of payloads) {
+    if (payload.type === "session.idle" || payload.type === "session.error") {
+      const sessionID = (payload as { properties?: { sessionID?: unknown } }).properties?.sessionID
+      if (typeof sessionID !== "string") continue
+      const update = pendingGlobalSessionUpdates.get(sessionID)
+      pendingGlobalSessionUpdates.delete(sessionID)
+      if (!update || update.runtimeKey !== runtimeKey) continue
+      const currentSession = overlay.get(sessionID) ?? null
+      if (
+        !currentSession
+        || shouldSkipStaleSessionEvent(currentSession, update.session)
+        || !isGlobalSessionRecencyOnlyUpdate(currentSession, update.session)
+      ) continue
+      appendUpsert(update.session)
+      flushedRecency = true
+      continue
+    }
+
+    if (payload.type === "session.created") {
+      const session = getSessionInfoFromPayload(payload)
+      if (session) {
+        const currentSession = overlay.get(session.id) ?? null
+        if (!shouldSkipStaleSessionEvent(currentSession, session)) appendUpsert(session)
+      }
+      continue
+    }
+
+    if (payload.type === "session.updated") {
+      const session = getSessionInfoFromPayload(payload)
+      if (session) {
+        const currentSession = overlay.get(session.id) ?? null
+        if (!shouldSkipStaleSessionEvent(currentSession, session)) {
+          if (currentSession && isGlobalSessionRecencyOnlyUpdate(currentSession, session)) {
+            scheduleGlobalSessionUpdate(session)
+          } else {
+            pendingGlobalSessionUpdates.delete(session.id)
+            appendUpsert(session)
+            streamPerfCount("ui.global_sessions.event_update_immediate")
+          }
+        }
+      }
+      continue
+    }
+
+    if (payload.type === "session.deleted") {
+      const sessionID = (payload as { properties?: { sessionID?: string } }).properties?.sessionID
+        ?? getSessionInfoFromPayload(payload)?.id
+      if (sessionID) {
+        pendingGlobalSessionUpdates.delete(sessionID)
+        overlay.delete(sessionID)
+        mutations.push({ type: "remove", sessionId: sessionID })
+      }
+    }
+  }
+
+  if (mutations.length === 0 || runtimeKey !== getRuntimeKey()) return
+  if (flushedRecency) streamPerfMark("global_sessions.event_update_flush")
+  store.applySessionMutations(mutations)
+  streamPerfCount("ui.global_sessions.event_update_publication")
 }
 
 export const applySessionEventToGlobalSessions = (payload: Event): void => {
-  if (payload.type === "session.idle" || payload.type === "session.error") {
-    const sessionID = (payload as { properties?: { sessionID?: unknown } }).properties?.sessionID
-    if (typeof sessionID === "string") flushPendingGlobalSessionUpdate(sessionID)
-    return
-  }
-
-  if (payload.type === "session.created") {
-    const session = getSessionInfoFromPayload(payload)
-    if (session) {
-      const currentSession = getGlobalSessionSnapshot(session.id)
-      if (!shouldSkipStaleSessionEvent(currentSession, session)) {
-        useGlobalSessionsStore.getState().upsertSession(session)
-      }
-    }
-    return
-  }
-
-  if (payload.type === "session.updated") {
-    const session = getSessionInfoFromPayload(payload)
-    if (session) {
-      const currentSession = getGlobalSessionSnapshot(session.id)
-      if (!shouldSkipStaleSessionEvent(currentSession, session)) {
-        if (currentSession && isGlobalSessionRecencyOnlyUpdate(currentSession, session)) {
-          scheduleGlobalSessionUpdate(session)
-        } else {
-          pendingGlobalSessionUpdates.delete(session.id)
-          useGlobalSessionsStore.getState().upsertSession(session)
-          streamPerfCount("ui.global_sessions.event_update_immediate")
-        }
-      }
-    }
-    return
-  }
-
-  if (payload.type === "session.deleted") {
-    const sessionID = (payload as { properties?: { sessionID?: string } }).properties?.sessionID ?? getSessionInfoFromPayload(payload)?.id
-    if (sessionID) {
-      pendingGlobalSessionUpdates.delete(sessionID)
-      useGlobalSessionsStore.getState().removeSessions([sessionID])
-    }
-  }
+  applySessionEventsToGlobalSessions([payload])
 }