Scott Moore presented on performance testing HTTP/3 (QUIC). He provided background on the timeline of HTTP/3 development and how it aims to solve head of line blocking that still exists with HTTP/2 over TCP. Moore demonstrated performance tests of HTTP/1.1, HTTP/2, and HTTP/3 with and without network emulation of LTE and satellite connections. The results showed HTTP/3's potential to remove head of line blocking but also challenges around increased server load and UDP optimizations needed. Moore concluded that HTTP/3 benefits will be most noticeable on low bandwidth connections and additional protocols will need to support it as adoption increases over time.

1. Performance Testing HTTP/3 (QUIC)
by SCOTT MOORE

2. Agenda
•HTTP/3 (QUIC) Timeline
•HTTP/3 Technical Breakdown
•HTTP/3 Challenges
•Demo
•Test Results and Findings
•Q&A
2

4. HTTP/3 TIMELINE

5. HTTP/2 AdptionRate
Source: HTTP/2 Adoption Dashboard (maintained by Telefónica Research, Case Western Reserve University,
and Carnegie Mellon University

6. HTTP/3 Timeline
• 2014 - Google deploys HTTP/2 over UDP. Calls it “QUIC”.
• November 2016 - Google takes QUIC to IETF. QUIC working group forms. Turned
into a Transport protocol.
• June 2018 - Google implements custom QUIC.
• November 2018
• Litespeed and Facebook test first functional HTTP/3 web server
• IETF changes the name for HTTP-over-QUIC to be HTTP/3
• April 2019 - Cloudflare releases Warp VPN based on QUIC draft
• July 2019 - HTTP/3 Draft expires at IETF
• August 2019 - Chromium fork released. Initial support for end-to-end iQUIC +
HTTP/3
• September 2019 - cURL, NGINX, Google Chrome show early HTTP/3 support
6

7. HTTP/2 Connection Versus HTTP 1.1
7
Image Source: Cloudflare

8. HTTP/3 ConnectionVersus HTTP/2
8
Image Source: Medium

9. WAIT....
Wasn't HTTP/2 multiplexing supposed to solve Head of Line Blocking?
HTTP level = YES. TCP level = NO.
Latency and Dropped Packets Expose This Problem.
QUIC is an attempt to fix it all once and for all...

10. HTTP/3 Stack
10
Image Source: Kinsta
TLS 1.3
1.2+

11. QLOG
11
• Log for QUIC and HTTP/3 events
• JSON Format
• Allows for debugging and visualization for QUIC streams
• Still being stanndardized
Image Source: Robin Marx

12. HTTP/3 Challenges

13. Challenges To Testing
•Lack of Support
•Draft code still has debugging (slower)
•Few Web Server Choices:
•LiteSpeed Enterprise (-not- OpenLiteSpeed)
•Caddy Server (VERY NEW)
•Cloudfare does not support it (yet)
13

14. Challenges forHTTP/3
•+/- 5% QUIC connections fail
•CPU Intensive - Requires 2X or more servers
•UDP on port 443 is blocked
•UDP is not as optimized as TCP
•No standard API for QUIC (yet)
14

15. HTTP/3 Tools
“Tools? Where we're going, we don't need tools.”
15

16. Tools
• cURL (after September 11, 2019)
• HTTP3 Check (http3check.net)
• QLog visualization tool (quicvis.edm.uhasselt.be/#/files)
• Browser Dev Tools
• Apposite Netropy
• Node JS and Puppeteer (??)
• Neotys Neoload
16

17. Current IETF QUIC Implementations
•AIOQUIC - Python
•lsquic - C - LiteSpeed
•ngtcp2 - C - open source effort
•QUICHE - RUST - Cloudflare
•Quiche - Google (because naming is hard)
•mvfst - C++ - Facebook
https://github.com/quicwg/base-drafts/wiki/Implementations
17

18. Demo - Test Results

20. The Mission
• Using a realistic web site,
compare:
• HTTP 1.1
• HTTP/2
• HTTP/3 (QUIC)
• Cloudflare/No Cloudflare
• Netropy Proxy
Determine:
• Is Head of Line Blocking gone?
20
https://loadtesthttp3.com

21. “I apologizefor the crudityofthis model...”
• Set up and configure cloud server instance (Ubuntu 18.04)
• Seperate Database (MySQL 8 on AWS RDS service)
• Litespeed web server with PHP 7.3
• Wordpress with custom theme
• Setup Domain, Email, and Cloudflare DNS/Caching
• Set up Network Emulation (Netropy Proxy)
• Baseline with GTMetrix, Web Page Test, Chrome DevTools
• Run up to 50 virtual users with NeoLoad
21

22. Chrome Waterfalls
22
HTTP 1.1 - 4.6 sec HTTP 2 - 0.5 sec H2 QUIC - 2.5 sec

23. Test Results - HTTP 1.1- No Network Emulation
23

24. Test Results - HTTP 2- No Network Emulation
24

25. Test Results - QUIC - No Network Emulationor Cloudflare
25

26. AddNetwork Emulation- LTE
26

27. AddNetwork Emulation- Satellite
27

28. Test Results - HTTP 1 -WITH Network Emulation LTE
28

29. Test Results - HTTP 1 -WITH Network Emulation - Satellite
29

30. Test Results - HTTP 2- WITH Network Emulation- LTE
30

31. Test Results - HTTP 2- WITH Network Emulation- Satellite
31

32. Test Results - QUIC - WITH Network Emulation- LTE
32

33. Test Results - QUIC - WITH Network Emulation- Satellite
33

34. Summary
• It SEEMS to remove HTTP HOL - but...
• Requires more server CPU/Memory
• Low Bandwidth situations benefit the most
• Will need to be tested as the spec evolves
• Test Cases Should include
Network Emulation
• TCP transition to UPD will be slow
• UDP will need to be optimized
• Additional protocols will come (i.e. DNS)
34

35. Who To Follow
• Robin Marx - @programmingart
• Daniel Stenberg (cURL) - @bagder
• Lucas Pardue - @SimmerVigor
• Barry Pollard - @tunetheweb
• Cloudflare
• LiteSpeed
• IETF
• Scott Moore - @loadtester
• Apposite Technologies - @Apposite_Tech
35

36. References
• CURL HTTP/3 library - https://github.com/curl/curl/blob/master/docs/HTTP3.md
• AIOQUIC - Python implementation. https://github.com/aiortc/aioquic.
• Cloudflare QUIC site: https://cloudflare-quic.com/
• QUIC Working group (IETF): https://quicwg.org/
• QLog visualization tool: https://quicvis.edm.uhasselt.be/#/files
• QUIC implementations: https://github.com/quicwg/base-drafts/wiki/Implementations
• HTTP/3 Verification Check (from LiteSpeed) - https://http3check.net/
36

37. http://scottmoore.consulting
help@scottmoore.consulting
Questionsand Contact