perf: reduce startup request fanout

Avoid repeated sidebar session and worktree refreshes
Limit concurrent GitHub PR status checks
Reuse cached worktree root resolution

packages/ui/src/components/session/SessionSidebar.tsx

@@ -360,6 +360,22 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     syncSessionsSnapshotRef.current = liveSessions;
   }, [syncSessionStructureSignature, liveSessions]);
 
+  const projectWorktreeDiscoveryKey = React.useMemo(
+    () => projects
+      .map((project) => `${project.id}:${normalizePath(project.path) ?? ''}`)
+      .join('|'),
+    [projects],
+  );
+
+  const initialGlobalSessionsRefreshStartedRef = React.useRef(false);
+  React.useEffect(() => {
+    if (initialGlobalSessionsRefreshStartedRef.current) {
+      return;
+    }
+    initialGlobalSessionsRefreshStartedRef.current = true;
+    void refreshGlobalSessions(syncSessionsSnapshotRef.current);
+  }, []);
+
   React.useEffect(() => {
     let cancelled = false;
 
@@ -397,13 +413,12 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
       });
     };
 
-    void refreshGlobalSessions(syncSessionsSnapshotRef.current);
     void discoverWorktrees();
 
     return () => {
       cancelled = true;
     };
-  }, [currentDirectory, syncSessionStructureSignature, projects]);
+  }, [projectWorktreeDiscoveryKey]);
 
   React.useEffect(() => {
     let refreshTimeout: ReturnType<typeof setTimeout> | null = null;
@@ -1113,7 +1128,6 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     });
 
     void refreshPrStatusTargets([...uniqueTargets.values()], {
-      force: true,
       silent: true,
       markInitialResolved: true,
     });

packages/ui/src/lib/worktrees/worktreeManager.ts

@@ -1,6 +1,5 @@
 import { substituteCommandVariables } from '@/lib/openchamberConfig';
 import type { WorktreeMetadata } from '@/types/worktree';
-import { execCommand } from '@/lib/execCommands';
 import {
   deleteRemoteBranch,
   git,
@@ -9,7 +8,7 @@ import {
   clearWorktreeBootstrapState,
   markWorktreeBootstrapPending,
 } from '@/lib/worktrees/worktreeBootstrap';
-import { invalidateResolvedProjectRootCache } from '@/lib/worktrees/worktreeStatus';
+import { invalidateResolvedProjectRootCache, resolveProjectRoot } from '@/lib/worktrees/worktreeStatus';
 import type {
   CreateGitWorktreePayload,
   GitWorktreeValidationResult,
@@ -55,66 +54,6 @@ const normalizePath = (value: string): string => {
   return replaced.length > 1 ? replaced.replace(/\/+$/, '') : replaced;
 };
 
-const toAbsolutePath = (baseDir: string, maybeRelativePath: string): string => {
-  const normalizedBase = normalizePath(baseDir);
-  const normalizedInput = normalizePath(maybeRelativePath);
-  if (!normalizedInput) return normalizedBase;
-  if (normalizedInput.startsWith('/')) return normalizedInput;
-
-  const stack = normalizedBase.split('/').filter(Boolean);
-  const parts = normalizedInput.split('/').filter(Boolean);
-  for (const part of parts) {
-    if (part === '.') continue;
-    if (part === '..') {
-      stack.pop();
-      continue;
-    }
-    stack.push(part);
-  }
-  return `/${stack.join('/')}`;
-};
-
-const derivePrimaryWorktreeRootFromGitDir = (gitDir: string): string | null => {
-  const normalized = normalizePath(gitDir);
-  if (!normalized) return null;
-  if (normalized.endsWith('/.git')) {
-    return normalized.slice(0, -'/.git'.length) || null;
-  }
-  const worktreesMarker = '/.git/worktrees/';
-  const markerIndex = normalized.indexOf(worktreesMarker);
-  if (markerIndex > 0) {
-    return normalized.slice(0, markerIndex) || null;
-  }
-  return null;
-};
-
-const resolvePrimaryWorktreeDirectory = async (directory: string): Promise<string> => {
-  const normalizedDirectory = normalizePath(directory);
-
-  const absoluteGitDirResult = await execCommand('git rev-parse --absolute-git-dir', normalizedDirectory);
-  const absoluteGitDir = normalizePath((absoluteGitDirResult.stdout || '').trim());
-  if (absoluteGitDirResult.success && absoluteGitDir) {
-    const rootFromAbsoluteGitDir = derivePrimaryWorktreeRootFromGitDir(absoluteGitDir);
-    if (rootFromAbsoluteGitDir) {
-      return rootFromAbsoluteGitDir;
-    }
-  }
-
-  const commonDirResult = await execCommand('git rev-parse --git-common-dir', normalizedDirectory);
-  const rawCommonDir = normalizePath((commonDirResult.stdout || '').trim());
-  if (!commonDirResult.success || !rawCommonDir) {
-    return normalizedDirectory;
-  }
-
-  const commonDir = toAbsolutePath(normalizedDirectory, rawCommonDir);
-  const rootFromCommonDir = derivePrimaryWorktreeRootFromGitDir(commonDir);
-  if (rootFromCommonDir) {
-    return rootFromCommonDir;
-  }
-
-  return normalizedDirectory;
-};
-
 const slugifyWorktreeName = (value: string): string => {
   return value
     .trim()
@@ -227,7 +166,7 @@ export async function listProjectWorktrees(project: ProjectRef): Promise<Worktre
   if (inflight) return inflight;
 
   const promise = (async (): Promise<WorktreeMetadata[]> => {
-    const metadataProjectDirectory = await resolvePrimaryWorktreeDirectory(projectDirectory).catch(() => projectDirectory);
+    const metadataProjectDirectory = await resolveProjectRoot(projectDirectory).catch(() => projectDirectory);
     const normalizedProjectDirectory = normalizePath(projectDirectory);
 
     const worktrees = await git.worktree.list(projectDirectory).catch(() => []);
@@ -289,7 +228,7 @@ export type CreateWorktreeArgs = {
 
 export async function createWorktree(project: ProjectRef, args: CreateWorktreeArgs): Promise<WorktreeMetadata> {
   const projectDirectory = normalizePath(project.path);
-  const metadataProjectDirectory = await resolvePrimaryWorktreeDirectory(projectDirectory).catch(() => projectDirectory);
+  const metadataProjectDirectory = await resolveProjectRoot(projectDirectory).catch(() => projectDirectory);
   const payload = toCreatePayload(args, projectDirectory);
 
   const created = await git.worktree.create(projectDirectory, payload);

packages/ui/src/lib/worktrees/worktreeStatus.ts

@@ -152,7 +152,7 @@ const computeProjectRoot = async (directory: string): Promise<string> => {
   return directory;
 };
 
-const resolveProjectRoot = async (directory: string): Promise<string> => {
+export const resolveProjectRoot = async (directory: string): Promise<string> => {
   const cached = resolvedRootCache.get(directory);
   if (cached && Date.now() - cached.resolvedAt < RESOLVED_ROOT_TTL_MS) {
     // Refresh recency without extending TTL.

packages/ui/src/stores/useGitHubPrStatusStore.ts

@@ -1,6 +1,7 @@
 import { create } from 'zustand';
 import { createJSONStorage, persist } from 'zustand/middleware';
 import type { GitHubPullRequestStatus, RuntimeAPIs } from '@/lib/api/types';
+import { mapWithConcurrency } from '@/lib/concurrency';
 import { getSafeStorage } from './utils/safeStorage';
 
 const PR_REVALIDATE_TTL_MS = 90_000;
@@ -10,6 +11,7 @@ const PR_BOOTSTRAP_RETRY_DELAYS_MS = [2_000, 5_000] as const;
 const PR_OPEN_BUSY_INTERVAL_MS = 60_000;
 const PR_OPEN_DEFAULT_INTERVAL_MS = 2 * 60_000;
 const PR_OPEN_STABLE_INTERVAL_MS = 5 * 60_000;
+const PR_STATUS_REFRESH_CONCURRENCY = 4;
 const PR_PERSIST_TTL_MS = 12 * 60 * 60_000;
 const PR_STATUS_STORAGE_KEY = 'openchamber.github-pr-status';
 
@@ -581,7 +583,7 @@ export const useGitHubPrStatusStore = create<GitHubPrStatusStore>()(
             .filter((key): key is string => Boolean(key)),
         ));
 
-        await Promise.all(keys.map((key) => get().refresh(key, options)));
+        await mapWithConcurrency(keys, PR_STATUS_REFRESH_CONCURRENCY, (key) => get().refresh(key, options));
       },
 
       updateStatus: (key, updater) => {

packages/ui/src/stores/useGlobalSessionsStore.ts

@@ -23,7 +23,7 @@ type GlobalSessionsState = {
   archiveSessions: (ids: Iterable<string>, archivedAt?: number) => void;
 };
 
-const PAGE_SIZE = 200;
+const PAGE_SIZE = 500;
 
 let inflightLoad: Promise<LoadResult> | null = null;
 

packages/ui/src/sync/sync-context.tsx

@@ -1569,6 +1569,9 @@ export function SyncProvider(props: {
           hasEverConnected: true,
           connectionPhase: "connected",
         })
+        if (isRecentBoot()) {
+          return
+        }
         for (const dir of childStores.children.keys()) {
           triggerDirectoryResync(dir)
         }

packages/ui/src/sync/use-sync.ts

@@ -35,6 +35,10 @@ const cmp = (a: string, b: string) => (a < b ? -1 : a > b ? 1 : 0)
 // session recency, not whichever component happened to call sync first.
 const seenByDirectory = new Map<string, Set<string>>()
 
+// Shared across useSync() hook instances. Chat, model controls, and sidebar can
+// all request the same session during startup; coalesce them into one HTTP load.
+const syncSessionInflightByKey = new Map<string, Promise<void>>()
+
 type SyncMeta = {
   limit: number
   cursor: string | undefined
@@ -99,7 +103,6 @@ export function useSync() {
   const childStores = useChildStoreManager()
 
   // Refs for mutable tracking (no re-renders)
-  const inflight = useRef(new Map<string, Promise<void>>())
   const optimistic = useRef(new Map<string, Map<string, OptimisticItem>>())
   const meta = useRef(new Map<string, SyncMeta>())
 
@@ -350,7 +353,7 @@ export function useSync() {
       const key = keyFor(sessionID)
 
       // Dedup inflight requests
-      const existing = inflight.current.get(key)
+      const existing = syncSessionInflightByKey.get(key)
       if (existing) return existing
 
       const current = store.getState()
@@ -386,35 +389,40 @@ export function useSync() {
         })) return
       }
 
+      const shouldFetchSession = !hasSession || force
+      const shouldLoadMessages = !cachedReady || force
       const promise = (async () => {
-        // Fetch session info if needed
-        if (!hasSession || force) {
-          try {
-            const result = await retry(() => sdk.session.get({ sessionID, directory }))
-            if (result.data) {
-              const s = store.getState()
-              const sessions = [...s.session]
-              const idx = Binary.search(sessions, sessionID, (s) => s.id)
-              if (idx.found) {
-                sessions[idx.index] = result.data
-              } else {
-                sessions.splice(idx.index, 0, result.data)
-              }
-              store.setState({ session: sessions })
-            }
-          } catch (e) {
-            console.error("[sync] failed to fetch session", sessionID, e)
-          }
-        }
-
-        // Load messages if needed
-        if (!cachedReady || force) {
-          await loadMessages(sessionID)
-        }
+        await Promise.all([
+          shouldFetchSession
+            ? (async () => {
+                try {
+                  const result = await retry(() => sdk.session.get({ sessionID, directory }))
+                  if (result.data) {
+                    const s = store.getState()
+                    const sessions = [...s.session]
+                    const idx = Binary.search(sessions, sessionID, (s) => s.id)
+                    if (idx.found) {
+                      sessions[idx.index] = result.data
+                    } else {
+                      sessions.splice(idx.index, 0, result.data)
+                    }
+                    store.setState({ session: sessions })
+                  }
+                } catch (e) {
+                  console.error("[sync] failed to fetch session", sessionID, e)
+                }
+              })()
+            : Promise.resolve(),
+          shouldLoadMessages ? loadMessages(sessionID) : Promise.resolve(),
+        ])
       })()
 
-      inflight.current.set(key, promise)
-      promise.finally(() => inflight.current.delete(key))
+      syncSessionInflightByKey.set(key, promise)
+      promise.finally(() => {
+        if (syncSessionInflightByKey.get(key) === promise) {
+          syncSessionInflightByKey.delete(key)
+        }
+      })
       return promise
     },
     [store, sdk, keyFor, touch, getMetaFor, setMetaFor, loadMessages, directory],