Comparing HTTP/3 vs. HTTP/2 Performance
So, as far as the results: In their synthetic benchmarks, they find negligible to no improvement:<p>&gt; For a small test page of 15KB, HTTP&#x2F;3 takes an average of 443ms to load compared to 458ms for HTTP&#x2F;2. However, once we increase the page size to 1MB that advantage disappears: HTTP&#x2F;3 is just slightly slower than HTTP&#x2F;2 on our network today, taking 2.33s to load versus 2.30s<p>And in their closer to real world benchmarks, they find no improvement, instead some negligible degradation.<p>&gt; As you can see, HTTP&#x2F;3 performance still trails HTTP&#x2F;2 performance, by about 1-4% on average in North America and similar results are seen in Europe, Asia and South America. We suspect this could be due to the difference in congestion algorithms: HTTP&#x2F;2 on BBR v1 vs. HTTP&#x2F;3 on CUBIC. In the future, we’ll work to support the same congestion algorithm on both to get a more accurate apples-to-apples comparison.<p>As a developer of web apps, I will personally continue to not think that much about HTTP&#x2F;3. Perhaps in the future network&#x2F;systems engineers will have figured out how to make it bear fruit? I don&#x27;t know, but it seems to me of unclear wisdom to count on it.