fix: speed up lifecycle transitions

README.md

@@ -136,6 +136,7 @@ This ensures in-progress context survives compaction and is visible in the next
 |----------|--------|---------|-------------|
 | `PI_MEMORY_QMD_UPDATE` | `background`, `manual`, `off` | `background` | Controls automatic `qmd update` after writes |
 | `PI_MEMORY_NO_SEARCH` | `1` | unset | Disable selective injection (for A/B testing) |
+| `PI_MEMORY_SUMMARIZE_TRANSITIONS` | `1`, `true`, `yes`, `on` | unset | Also write exit summaries during lifecycle transitions (`/reload`, `/new`, `/resume`, `/fork`). By default these transitions skip summaries for speed. |
 
 ## Running tests
 

index.ts

@@ -443,6 +443,17 @@ function getQmdUpdateMode(): "background" | "manual" | "off" {
 	return "background";
 }
 
+export function shouldSummarizeLifecycleTransitions(): boolean {
+	const value = (process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS ?? "").toLowerCase();
+	return value === "1" || value === "true" || value === "yes" || value === "on";
+}
+
+export function shouldSkipExitSummaryForReason(reason: string | undefined): boolean {
+	if (!reason) return false;
+	if (shouldSummarizeLifecycleTransitions()) return false;
+	return ["reload", "new", "resume", "fork"].includes(reason);
+}
+
 async function ensureQmdAvailableForUpdate(): Promise<boolean> {
 	if (qmdAvailable) return true;
 	if (getQmdUpdateMode() !== "background") return false;
@@ -596,6 +607,9 @@ type ExecFileFn = typeof execFile;
 let execFileFn: ExecFileFn = execFile;
 
 let qmdAvailable = false;
+let qmdAvailabilityCheckedAt = 0;
+const QMD_STATUS_CACHE_TTL_MS = 5 * 60 * 1000;
+const qmdCollectionStatusCache = new Map<string, { checkedAt: number; exists: boolean }>();
 let updateTimer: ReturnType<typeof setTimeout> | null = null;
 let exitSummaryReason: ExitSummaryReason | null = null;
 let terminalInputUnsubscribe: (() => void) | null = null;
@@ -613,6 +627,7 @@ export function _resetExecFileForTest() {
 /** Set qmd availability flag (for testing). */
 export function _setQmdAvailable(value: boolean) {
 	qmdAvailable = value;
+	qmdAvailabilityCheckedAt = Date.now();
 }
 
 /** Get current qmd availability flag (for testing). */
@@ -633,6 +648,12 @@ export function _clearUpdateTimer() {
 	}
 }
 
+/** Clear qmd status caches (for testing). */
+export function _clearQmdStatusCaches() {
+	qmdAvailabilityCheckedAt = 0;
+	qmdCollectionStatusCache.clear();
+}
+
 const QMD_REPO_URL = "https://github.com/tobi/qmd";
 
 export function qmdInstallInstructions(): string {
@@ -692,41 +713,53 @@ export async function setupQmdCollection(): Promise<boolean> {
 }
 
 export function detectQmd(): Promise<boolean> {
+	const now = Date.now();
+	if (qmdAvailabilityCheckedAt && now - qmdAvailabilityCheckedAt < QMD_STATUS_CACHE_TTL_MS) {
+		return Promise.resolve(qmdAvailable);
+	}
+
 	return new Promise((resolve) => {
 		// qmd doesn't reliably support --version; use a fast command that exits 0 when available.
 		execFileFn("qmd", ["status"], { timeout: 5_000 }, (err) => {
-			resolve(!err);
+			qmdAvailable = !err;
+			qmdAvailabilityCheckedAt = Date.now();
+			resolve(qmdAvailable);
 		});
 	});
 }
 
 export function checkCollection(name: string): Promise<boolean> {
+	const cached = qmdCollectionStatusCache.get(name);
+	const now = Date.now();
+	if (cached && now - cached.checkedAt < QMD_STATUS_CACHE_TTL_MS) {
+		return Promise.resolve(cached.exists);
+	}
+
 	return new Promise((resolve) => {
 		execFileFn("qmd", ["collection", "list", "--json"], { timeout: 10_000 }, (err, stdout) => {
-			if (err) {
-				resolve(false);
-				return;
-			}
-			try {
-				const collections = JSON.parse(stdout);
-				if (Array.isArray(collections)) {
-					resolve(
-						collections.some((entry) => {
+			let exists = false;
+			if (!err) {
+				try {
+					const collections = JSON.parse(stdout);
+					if (Array.isArray(collections)) {
+						exists = collections.some((entry) => {
 							if (typeof entry === "string") return entry === name;
 							if (entry && typeof entry === "object" && "name" in entry) {
 								return (entry as { name?: string }).name === name;
 							}
 							return false;
-						}),
-					);
-				} else {
-					// qmd may output an object with a collections array or similar
-					resolve(stdout.includes(name));
+						});
+					} else {
+						// qmd may output an object with a collections array or similar
+						exists = stdout.includes(name);
+					}
+				} catch {
+					// Fallback: just check if the name appears in the output
+					exists = stdout.includes(name);
 				}
-			} catch {
-				// Fallback: just check if the name appears in the output
-				resolve(stdout.includes(name));
 			}
+			qmdCollectionStatusCache.set(name, { checkedAt: Date.now(), exists });
+			resolve(exists);
 		});
 	});
 }
@@ -907,10 +940,18 @@ export default function (pi: ExtensionAPI) {
 			terminalInputUnsubscribe = null;
 		}
 
-		// /reload emits session_shutdown with reason "reload" before rebuilding the
-		// runtime. Generating an exit summary here would make every /reload block
-		// for several seconds on a live LLM call. Skip it — the session continues.
-		if (event.reason === "reload") {
+		// Lifecycle transitions are usually not final session exits. By default,
+		// avoid generating LLM summaries and running qmd updates during /reload,
+		// /new, /resume, and /fork because that makes those transitions slow.
+		// Users who prefer the old behavior can opt in with
+		// PI_MEMORY_SUMMARIZE_TRANSITIONS=1.
+		const shutdownReason = (event as { reason?: string }).reason;
+		if (shouldSkipExitSummaryForReason(shutdownReason)) {
+			exitSummaryReason = null;
+			if (updateTimer) {
+				clearTimeout(updateTimer);
+				updateTimer = null;
+			}
 			return;
 		}
 

test/qmd-cache.ts

@@ -0,0 +1,76 @@
+import { strict as assert } from "node:assert";
+import type { execFile } from "node:child_process";
+import {
+	_clearQmdStatusCaches,
+	_resetExecFileForTest,
+	_setExecFileForTest,
+	_setQmdAvailable,
+	checkCollection,
+	detectQmd,
+	shouldSkipExitSummaryForReason,
+} from "../index.ts";
+
+type ExecFileFn = typeof execFile;
+
+type ExecCallback = (error: Error | null, stdout: string, stderr: string) => void;
+
+function mockExecFile(handler: (cmd: string, args: readonly string[]) => { error?: Error; stdout?: string }) {
+	let calls = 0;
+	const fn: ExecFileFn = ((cmd: string, args: readonly string[], _options: unknown, callback: ExecCallback) => {
+		calls++;
+		const result = handler(cmd, args);
+		queueMicrotask(() => callback(result.error ?? null, result.stdout ?? "", ""));
+	}) as ExecFileFn;
+	_setExecFileForTest(fn);
+	return () => calls;
+}
+
+try {
+	_clearQmdStatusCaches();
+	const qmdCalls = mockExecFile((cmd, args) => {
+		assert.equal(cmd, "qmd");
+		assert.deepEqual(args, ["status"]);
+		return {};
+	});
+
+	assert.equal(await detectQmd(), true);
+	assert.equal(await detectQmd(), true);
+	assert.equal(qmdCalls(), 1, "detectQmd should cache qmd status within the TTL");
+
+	_clearQmdStatusCaches();
+	const collectionCalls = mockExecFile((cmd, args) => {
+		assert.equal(cmd, "qmd");
+		assert.deepEqual(args, ["collection", "list", "--json"]);
+		return { stdout: JSON.stringify([{ name: "pi-memory" }]) };
+	});
+
+	assert.equal(await checkCollection("pi-memory"), true);
+	assert.equal(await checkCollection("pi-memory"), true);
+	assert.equal(collectionCalls(), 1, "checkCollection should cache collection lookup within the TTL");
+
+	_setQmdAvailable(false);
+	assert.equal(await detectQmd(), false, "_setQmdAvailable should seed the cached status");
+
+	const originalSummarizeTransitions = process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS;
+	try {
+		delete process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS;
+		assert.equal(shouldSkipExitSummaryForReason("reload"), true);
+		assert.equal(shouldSkipExitSummaryForReason("new"), true);
+		assert.equal(shouldSkipExitSummaryForReason("session-end"), false);
+
+		process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS = "1";
+		assert.equal(shouldSkipExitSummaryForReason("reload"), false);
+		assert.equal(shouldSkipExitSummaryForReason("new"), false);
+	} finally {
+		if (originalSummarizeTransitions === undefined) {
+			delete process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS;
+		} else {
+			process.env.PI_MEMORY_SUMMARIZE_TRANSITIONS = originalSummarizeTransitions;
+		}
+	}
+
+	console.log("qmd cache tests passed");
+} finally {
+	_resetExecFileForTest();
+	_clearQmdStatusCaches();
+}