HTTP/2: The Weird Parts

Transcript

1. HTTP/2: The Weird Parts
   @smithclay / New Relic
   ScotlandJS 2016
   

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2. ScotlandJS 2016 @smithclay / New Relic
   What this talk isn't about
   • Code
   • Implementing HTTP/2 in Production
   • How HTTP/2 will totally, absolutely solve
   every performance problem (it won't).
   • H2 = HTTP/2
   

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3. ScotlandJS 2016 @smithclay / New Relic
   Me Server
   HTTP
   San Francisco Northern Virginia
   

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4. ScotlandJS 2016 @smithclay / New Relic
   Me
   HTTP
   Server
   San Francisco Northern Virginia
   Person
   Paris
   HTTP
   

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5. ScotlandJS 2016 @smithclay / New Relic
   Me
   ~40 ms roundtrip*
   Server
   San Francisco Northern Virginia
   Person
   Paris
   ~ 88ms roundtrip*
   *http://www.timbercon.com/time-delay-of-light-in-fiber-calculator/
   *calculated using great-circle distance in fiber (not real life)
   

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6. ScotlandJS 2016 @smithclay / New Relic
   More RTs, more latency
   Browser Server
   Data Transfer
   {
   Round trip
   1. SYN
   2. SYN/ACK
   3. ACK
   {
   {
   TLS
   Full TCP + TLS (i.e. HTTPS) handshake
   TCP
   Handshake
   Cool TLS Demo: https://tls.openmirage.org/
   

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7. ScotlandJS 2016 @smithclay / New Relic
   http://httparchive.org/trends.php?s=All&minlabel=May+15+2014&maxlabel=May+15+2016#_connections
   2014 2016
   

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8. ScotlandJS 2016 @smithclay / New Relic
   http://httparchive.org/trends.php?s=All&minlabel=May+15+2014&maxlabel=May
   +15+2016#numDomains&maxDomainReqs
   2014 2016
   

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9. Making things better
   with HTTP/2
   

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10. ScotlandJS 2016 @smithclay / New Relic
    

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11. ScotlandJS 2016 @smithclay / New Relic
    HTTP/2 has 10 frame types
    FRAME FRAME
    FRAME FRAME
    FRAME
    FRAME FRAME
    Stream 0
    Stream 1
    Stream 2
    Frames get reassembled into standard request/response messages
    

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12. ScotlandJS 2016 @smithclay / New Relic
    Front-end implications*
    Ciao
    Concatenation
    Sianara
    Sharding and
    Spriting
    Bye
    Inlining
    *Assuming most of your traffic has HTTP/2 capable browsers.
    https://blog.newrelic.com/2016/02/09/http2-best-practices-web-performance/
    

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13. The Weird Frames
    

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14. ScotlandJS 2016 @smithclay / New Relic
    PUSH_PROMISE FRAME
    • Not websockets
    replacement.
    • Intention to send responses.
    • https://www.w3.org/TR/
    preload/#server-push-http-2
    HTTP Request Precognition
    YOU
    WILL WANT THIS
    

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15. ScotlandJS 2016 @smithclay / New Relic
    GOAWAY FRAME
    • Terminates the TCP
    connection.
    • Helps clients know what
    streams might not be
    processed.
    NO
    THANKS
    

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16. ScotlandJS 2016 @smithclay / New Relic
    PING FRAME
    • Safely tests the connection
    without a request.
    • "A mechanism for measuring
    a minimal round-trip time
    from the sender, as well as
    determining whether an idle
    connection is still
    functional."
    STILL THERE?
    

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17. More frame types to
    come...
    https://tools.ietf.org/wg/httpbis/
    

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18. ScotlandJS 2016 @smithclay / New Relic
    Takeaways
    Measure
    & Profile*
    Reduce
    Connections
    Design for
    latency
    CDNs:
    close to your
    users
    *http://wireshark.com/
    https://mitmproxy.org/
    

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19. ScotlandJS 2016 @smithclay / New Relic
    #perfforthepeople
    

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20. Thanks
    @smithclay / New Relic
    ScotlandJS 2016
    

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21. ScotlandJS 2016 @smithclay / New Relic
    Additional information
    • Go read High Performance Browser Networking (it's great).
    • https://daniel.haxx.se/http2/
    • https://newrelic.com/browser
    • https://blogs.dropbox.com/tech/2016/05/enabling-http2-for-dropbox-web-
    services-experiences-and-observations/
    • http://engineering.khanacademy.org/posts/js-packaging-http2.htm
    • https://blog.newrelic.com/2016/02/09/http2-best-practices-web-
    performance/
    

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