Promise of Push - Speaker Deck

Slide 1

Slide 1 text

Slide 2

Slide 2 text

Slide 3

Slide 3 text

Slide 4

Slide 4 text

Grow revenue opportunities with fast, personalized web experiences and manage complexity from peak demand, mobile devices and data collection. ©2016 AKAMAI | FASTER FORWARD™ Chapter 1: What is (h2) PUSH?

Slide 5

Slide 5 text

Slide 6

Slide 6 text

Slide 7

Slide 7 text

©2016 AKAMAI | FASTER FORWARD™ #PerfMatters Perf 101 Wait ├ Caching ├ Protocol opt ├ Route opt. ├ Sharding └ Use time machine ├ webpack / concat ├ spriting / inlining ├ lazyload └ Reqs ├ Critical CSS ├ javascript ├ AMP └ Chroma Sub-Sampling Render Bits ├ gzip/br ├ Resp. img ├ jp2 /webp └ webfonts

Slide 8

Slide 8 text

Slide 9

Slide 9 text

Slide 10

Slide 10 text

Slide 11

Slide 11 text

Slide 12

Slide 12 text

Slide 13

Slide 13 text

Slide 14

Slide 14 text

Slide 15

Slide 15 text

How to PUSH Polling / Long Polling GET /messages HTTP/1.1 Host: queue.example.com Authorization: ... HTTP/1.1 200 OK Content-Length: 100 { "from": "[email protected]", "to": "[email protected]", "message: "Do you bite your thumb at us, sir? }

Slide 16

Slide 16 text

©2016 AKAMAI | FASTER FORWARD™ One-to-One with WebSockets var ws = new WebSocket('wss://example.com/socket'); ws.onmessage = function(msg) { if(msg.data instanceof Blob) { processBlob(msg.data); } else { processText(msg.data); } } function sendMessage(msgText) { ws.send(msgText); } Not cacheable; meant for special apps, not webpages

Slide 17

Slide 17 text

Slide 18

Slide 18 text

©2016 AKAMAI | FASTER FORWARD™ How to PUSH Server-Side-Events GET /messages HTTP/1.1 Host: api.example.com Accept: text/event-stream Authorization: ... Last-Event-ID: 41 HTTP/1.1 200 OK Connection: keep-alive Content-Type: text/event-stream Transfer-Encoding: chunked id: 42 event: receiveMessage data: { "from": "[email protected]", "to": "[email protected]", "message: "Do you bite your thumb at us, sir?} id: 43 event: stageAction data: { "from": "[email protected]", "to": "[email protected]", "message: "Do you bite your thumb at us, sir?}

Slide 19

Slide 19 text

©2016 AKAMAI | FASTER FORWARD™ How to PUSH Server-Side-Events HTTP/1.1 200 OK Connection: keep-alive Content-Type: text/event-stream Transfer-Encoding: chunked id: 42 event: recieveMessage data: { "from": "[email protected]", "to": "[email protected]", "message: "Do you bite your thumb at us, sir?} id: 43 event: stageAction data: { "from": "[email protected]", "to": "[email protected]", "message: "Do you bite your thumb at us, sir?} var evtSource = new EventSource("/messages"); evtSource.addEventListener("receiveMessage", function(e) { var newElement = document.createElement("p"); var obj = JSON.parse(e.data); newElement.innerHTML = "Message: " + obj.message; eventList.appendChild(newElement); }, false); Close – but realtime & text only (not resources)

Slide 20

Slide 20 text

Slide 21

Slide 21 text

Slide 22

Slide 22 text

Slide 23

Slide 23 text

Slide 24

Slide 24 text

Slide 25

Slide 25 text

Slide 26

Slide 26 text

HTTP/2 PUSH_PROMISE Frame Basics DATA a:hover {color: blue} … PUSH_PROMISE :url: /push.css user-agent: chrome HEADERS :method: GET … SETTINGS ENABLE_PUSH: 0 RST_STREAM HEADERS :status: 200 …

Slide 27

Slide 27 text

HTTP/2 PUSH_PROMISE Expected Lifecycle HEADERS 13 HEADERS 13 DATA 13 PUSH_PROMISE 13 promised-stream-id: 2 HEADERS 2 DATA 2 … wait ...

Slide 28

Slide 28 text

HTTP/2 PUSH_PROMISE Expected Lifecycle HEADERS 13 HEADERS 13 DATA 13 PUSH_PROMISE 13 promised-stream-id: 2 RST_STREAM 2

Slide 29

Slide 29 text

©2016 AKAMAI | FASTER FORWARD™ HTTP/2 PUSH_PROMISE $ nghttp https://www.colinbendell.com/demo/h2/pushtest.html -vv --no-push [ 0.123] Connected The negotiated protocol: h2 [ 0.518] send SETTINGS frame (niv=3) [SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100] [SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535] [SETTINGS_ENABLE_PUSH(0x02):0] Push Not Supported [ 0.230] send RST_STREAM frame Push not accepted

Slide 30

Slide 30 text

Slide 31

Slide 31 text

HTTP/2 PUSH Browsers & Apps Browser GET /index.html PUSH /global.css GET /index.html Cache Secret Queue* Unused Streams

Slide 32

Slide 32 text

HTTP/2 PUSH in a Secret Cache / Queue Browsers & Apps Browser GET /global.css Cache Unused Streams

Slide 33

Slide 33 text

Slide 34

Slide 34 text

Slide 35

Slide 35 text

chrome://net-internals

Slide 36

Slide 36 text

©2016 AKAMAI | FASTER FORWARD™ HTTP/2 (Chrome) Adopted Push Stream chrome://net-internals to find unclaimed pushes Adopted pushes are logged (not a frame) * PUSH is kept in memory for 5 minutes and then get deleted if unclaimed

Slide 37

Slide 37 text

Slide 38

Slide 38 text

Slide 39

Slide 39 text

canipush.com Browser Test Harness Browser GET /example.css PUSH /example.css Cache Unused Streams ? Different content

Slide 40

Slide 40 text

Slide 41

Slide 41 text

Slide 42

Slide 42 text

Slide 43

Slide 43 text

Slide 44

Slide 44 text

Slide 45

Slide 45 text

Slide 46

Slide 46 text

Slide 47

Slide 47 text

Slide 48

Slide 48 text

Slide 49

Slide 49 text

Slide 50

Slide 50 text

Slide 51

Slide 51 text

Slide 52

Slide 52 text

©2016 AKAMAI | FASTER FORWARD™ Browser Support Implementation notes • Cross Origin XHR are different • PUSHed content must be pulled (no programatic alerting – use SSE for that) • FF uses init flow control of 64kb • Browsers don’t (yet) sync caches

Slide 53

Slide 53 text

Slide 54

Slide 54 text

Slide 55

Slide 55 text

Slide 56

Slide 56 text

Slide 57

Slide 57 text

Slide 58

Slide 58 text

Slide 59

Slide 59 text

©2016 AKAMAI | FASTER FORWARD™ How do you push? Hint (late) with Headers HTTP/2 200 OK Content-Type: text/html Link: /jquery.js; rel=preload; as=script Link: /global.css; rel=preload; as=style; nopush Link: ; rel=preload; as=style

Slide 60

Slide 60 text

Slide 61

Slide 61 text

Slide 62

Slide 62 text

Slide 63

Slide 63 text

HTTP/2 PUSH_PROMISE Why can't you send Link early? DATA a:hover {color: blue} … HEADERS :method: GET … HEADERS :status: 200 Link: ... rel=preload

Slide 64

Slide 64 text

Slide 65

Slide 65 text

©2016 AKAMAI | FASTER FORWARD™ RFC 7540: The server SHOULD send PUSH_PROMISE (Section 6.6) frames prior to sending any frames that reference the promised responses. This avoids a race where clients issue requests prior to receiving any PUSH_PROMISE frames.

Slide 66

Slide 66 text

©2016 AKAMAI | FASTER FORWARD™ How do you push? Push while waiting public class MyServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) { String uri = request.getRequestURI(); if ("/index.html".equals(uri)) { String resourceToPush = "/js/jquery.js"; RequestDispatcher dispatcher = request.getRequestDispatcher(resourceToPush); dispatcher.push(request); } } }

Slide 67

Slide 67 text

Slide 68

Slide 68 text

Slide 69

Slide 69 text

Slide 70

Slide 70 text

Slide 71

Slide 71 text

©2016 AKAMAI | FASTER FORWARD™ https://goo.gl/M98bWr Google' Recommendations 1. Push just enough to fill idle network time, and no more 2. Push resources in right order. 3. Use special strategies to track the client-side cache 4. Use the right cookies when pushing resources that vary by cookie 5. Use server push to fill the initial cwnd and use preload to reveal the remaining critical or hidden resources.

Slide 72

Slide 72 text

No content

Slide 73

Slide 73 text

Slide 74

Slide 74 text

Slide 75

Slide 75 text

Slide 76

Slide 76 text

Slide 77

Slide 77 text

Slide 78

Slide 78 text

Slide 79

Slide 79 text

Slide 80

Slide 80 text

Slide 81

Slide 81 text

Slide 82

Slide 82 text

©2016 AKAMAI | FASTER FORWARD™ PUSH Questions & Predictions • First request: ClientHints, Session Cookies • PUSH to surrogate but not client • Cache Management / Invalidation • Next page resources • DDOS countermeasures using PUSH

Slide 83

Slide 83 text

Slide 84

Slide 84 text

©2016 AKAMAI | FASTER FORWARD™ HTTP/2 PUSH Take Action Optimize for the Browser • Cache Everything • Remove 3rd Party Content • Federated development: move APIs to the 1st party domain • Plan for coalescing (use TLS SANs) Experiment • shouldipush.com • Test TTFB globally

Slide 85

Slide 85 text