fix: undo timeout change to fix performance regression

cli/CHANGELOG.md

@@ -1,4 +1,12 @@
 <!-- See the ../guides/writing-the-cypress-changelog.md for details on writing the changelog. -->
+## 13.3.2
+
+_Released 10/18/2023 (PENDING)_
+
+**Bugfixes:**
+
+- Fixed a performance regression where proxy correlation timeouts for requests in service workers were always hit causing slow downs. Fixes [#28054](https://github.com/cypress-io/cypress/issues/28054)
+
 ## 13.3.1
 
 _Released 10/11/2023_

packages/proxy/lib/http/util/prerequests.ts

@@ -51,12 +51,12 @@ class QueueMap<T> {
 
     this.queues[queueKey].push(value)
   }
-  shift (queueKey: string): T | undefined {
+  pop (queueKey: string): T | undefined {
     const queue = this.queues[queueKey]
 
     if (!queue) return
 
-    const item = queue.shift()
+    const item = queue.pop()
 
     if (queue.length === 0) delete this.queues[queueKey]
 
@@ -95,7 +95,7 @@ export class PreRequests {
   protocolManager?: ProtocolManagerShape
 
   constructor (
-    requestTimeout = 2000,
+    requestTimeout = 500,
     // 10 seconds
     sweepInterval = 10000,
   ) {
@@ -134,7 +134,7 @@ export class PreRequests {
   addPending (browserPreRequest: BrowserPreRequest) {
     metrics.browserPreRequestsReceived++
     const key = `${browserPreRequest.method}-${browserPreRequest.url}`
-    const pendingRequest = this.pendingRequests.shift(key)
+    const pendingRequest = this.pendingRequests.pop(key)
 
     if (pendingRequest) {
       const timings = {
@@ -174,7 +174,7 @@ export class PreRequests {
 
   addPendingUrlWithoutPreRequest (url: string) {
     const key = `GET-${url}`
-    const pendingRequest = this.pendingRequests.shift(key)
+    const pendingRequest = this.pendingRequests.pop(key)
 
     if (pendingRequest) {
       debugVerbose('Handling %s without a CDP prerequest', key)
@@ -200,7 +200,7 @@ export class PreRequests {
 
     metrics.proxyRequestsReceived++
     const key = `${req.method}-${req.proxiedUrl}`
-    const pendingPreRequest = this.pendingPreRequests.shift(key)
+    const pendingPreRequest = this.pendingPreRequests.pop(key)
 
     if (pendingPreRequest) {
       metrics.immediatelyMatchedRequests++
@@ -217,7 +217,7 @@ export class PreRequests {
       return
     }
 
-    const pendingUrlWithoutPreRequests = this.pendingUrlsWithoutPreRequests.shift(key)
+    const pendingUrlWithoutPreRequests = this.pendingUrlsWithoutPreRequests.pop(key)
 
     if (pendingUrlWithoutPreRequests) {
       metrics.immediatelyMatchedRequests++

packages/proxy/test/unit/http/util/prerequests.spec.ts

@@ -41,28 +41,29 @@ describe('http/util/prerequests', () => {
       cdpRequestWillBeSentReceivedTimestamp: 2,
     })
 
-    const secondPreRequest: BrowserPreRequest = {
+    preRequests.addPending({
       requestId: '1234',
       url: 'foo',
       method: 'GET',
       headers: {},
       resourceType: 'xhr',
       originalResourceType: undefined,
       cdpRequestWillBeSentTimestamp: 1,
-      cdpRequestWillBeSentReceivedTimestamp: performance.now() + performance.timeOrigin + 10000,
-    }
+      cdpRequestWillBeSentReceivedTimestamp: 2,
+    })
 
-    preRequests.addPending(secondPreRequest)
-    preRequests.addPending({
+    const thirdRequest: BrowserPreRequest = {
       requestId: '1234',
       url: 'foo',
       method: 'GET',
       headers: {},
       resourceType: 'xhr',
       originalResourceType: undefined,
       cdpRequestWillBeSentTimestamp: 1,
-      cdpRequestWillBeSentReceivedTimestamp: 2,
-    })
+      cdpRequestWillBeSentReceivedTimestamp: performance.now() + performance.timeOrigin + 10000,
+    }
+
+    preRequests.addPending(thirdRequest)
 
     expectPendingCounts(0, 3)
 
@@ -73,17 +74,17 @@ describe('http/util/prerequests', () => {
     const { args } = cb.getCall(0)
     const arg = args[0]
 
-    expect(arg.requestId).to.eq(secondPreRequest.requestId)
-    expect(arg.url).to.eq(secondPreRequest.url)
-    expect(arg.method).to.eq(secondPreRequest.method)
-    expect(arg.headers).to.deep.eq(secondPreRequest.headers)
-    expect(arg.resourceType).to.eq(secondPreRequest.resourceType)
-    expect(arg.originalResourceType).to.eq(secondPreRequest.originalResourceType)
-    expect(arg.cdpRequestWillBeSentTimestamp).to.eq(secondPreRequest.cdpRequestWillBeSentTimestamp)
-    expect(arg.cdpRequestWillBeSentReceivedTimestamp).to.eq(secondPreRequest.cdpRequestWillBeSentReceivedTimestamp)
+    expect(arg.requestId).to.eq(thirdRequest.requestId)
+    expect(arg.url).to.eq(thirdRequest.url)
+    expect(arg.method).to.eq(thirdRequest.method)
+    expect(arg.headers).to.deep.eq(thirdRequest.headers)
+    expect(arg.resourceType).to.eq(thirdRequest.resourceType)
+    expect(arg.originalResourceType).to.eq(thirdRequest.originalResourceType)
+    expect(arg.cdpRequestWillBeSentTimestamp).to.eq(thirdRequest.cdpRequestWillBeSentTimestamp)
+    expect(arg.cdpRequestWillBeSentReceivedTimestamp).to.eq(thirdRequest.cdpRequestWillBeSentReceivedTimestamp)
     expect(arg.proxyRequestReceivedTimestamp).to.be.a('number')
-    expect(arg.cdpLagDuration).to.eq(secondPreRequest.cdpRequestWillBeSentReceivedTimestamp - secondPreRequest.cdpRequestWillBeSentTimestamp)
-    expect(arg.proxyRequestCorrelationDuration).to.eq(secondPreRequest.cdpRequestWillBeSentReceivedTimestamp - arg.proxyRequestReceivedTimestamp)
+    expect(arg.cdpLagDuration).to.eq(thirdRequest.cdpRequestWillBeSentReceivedTimestamp - thirdRequest.cdpRequestWillBeSentTimestamp)
+    expect(arg.proxyRequestCorrelationDuration).to.eq(thirdRequest.cdpRequestWillBeSentReceivedTimestamp - arg.proxyRequestReceivedTimestamp)
 
     expectPendingCounts(0, 2)
   })