@@ -742,7 +742,10 @@ export class Socket<
 debug("closing socket - reason %s", reason);
 this.emitReserved("disconnecting", reason, description);
 
-if (RECOVERABLE_DISCONNECT_REASONS.has(reason)) {
+if (
+this.server._opts.connectionStateRecovery &&
+RECOVERABLE_DISCONNECT_REASONS.has(reason)
+) {
 debug("connection state recovery is enabled for sid %s", this.id);
 this.adapter.persistSession({
 sid: this.id,

@@ -2,6 +2,7 @@ import { Server, Socket } from "..";
 import expect from "expect.js";
 import { waitFor, eioHandshake, eioPush, eioPoll } from "./support/util";
 import { createServer, Server as HttpServer } from "http";
+import { Adapter } from "socket.io-adapter";
 
 async function init(httpServer: HttpServer, io: Server) {
 // Engine.IO handshake
@@ -215,4 +216,32 @@ describe("connection state recovery", () => {
 
 io.close();
 });
+
+it("should not call adapter#persistSession or adapter#restoreSession if disabled", async () => {
+const httpServer = createServer().listen(0);
+
+class DummyAdapter extends Adapter {
+override persistSession(session) {
+expect.fail();
+}
+
+override restoreSession(pid, offset) {
+expect.fail();
+return Promise.reject("should not happen");
+}
+}
+
+const io = new Server(httpServer, {
+adapter: DummyAdapter,
+});
+
+// Engine.IO handshake
+const sid = await eioHandshake(httpServer);
+
+await eioPush(httpServer, sid, '40{"pid":"foo","offset":"bar"}');
+await eioPoll(httpServer, sid);
+await eioPush(httpServer, sid, "1");
+
+io.close();
+});
 });