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Go 1.27 makes repeated HTTP/1 requests nearly five times faster

go.dev 7 min read Editor score 8/10

A sample program’s runtime against index.golang.org fell from about 710 ms on Go 1.26 to 150 ms on Go 1.27, attributed to better connection reuse. The improvement illustrates how connection setup costs can dominate latency in network clients.

What: - Go 1.27 improves HTTP/1 connection reuse; a 100-request test in the excerpt fell from about 710 ms on Go 1.26 to about 150 ms.
How: - TCP and TLS handshakes add round trips, while HTTP/1 requests and responses share a sequential byte stream and connections can be reused.
Why it matters: - For latency-sensitive clients, connection reuse avoids setup costs that can outweigh the time needed to serve a request.

A new connection completes TCP and TLS handshakes before the HTTP request is sent. Sketched from the article's own text.

Read on go.dev → Hacker News · 34 comments Lobsters

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