The bandwidth reduction is due to use of a binary protocol, not Go. It just so happens the server code is written in Go and C.
From the article:
“Go is very light,” he said, “and it has fundamental support for concurrent programming. And it’s surprisingly stable for a young language. The experience has been extremely good—there have been no problems with deadlocks or pointer exceptions.” But the code hit a bit of a performance bottleneck under CloudFlare’s heavy loads, particularly because of its cryptographic modules—all of Railgun’s traffic is encrypted from end to end. “We swapped some things out into C just from a performance perspective," Graham-Cumming said.
“We want Go to be as fast as C for these things,” he explained, and in the long term he believes Go’s cryptographic modules will mature and get better. But in the meantime, “we swapped out Go’s native crypto for OpenSSL,” he said, using assembly language versions of the C libraries.
On another note, it's always nice to see such an influential part of the HN community giving quotes for sites like this - not only does it make me a little proud to be associated with any of you, it makes me more hopeful for the chances of my future that I can call myself one of us.
The binary protocol means we don't add (much) overhead, the bandwidth reduction is because we are sending page diffs which themselves are encoded in a compact binary format.
From the article:
“Go is very light,” he said, “and it has fundamental support for concurrent programming. And it’s surprisingly stable for a young language. The experience has been extremely good—there have been no problems with deadlocks or pointer exceptions.” But the code hit a bit of a performance bottleneck under CloudFlare’s heavy loads, particularly because of its cryptographic modules—all of Railgun’s traffic is encrypted from end to end. “We swapped some things out into C just from a performance perspective," Graham-Cumming said.
“We want Go to be as fast as C for these things,” he explained, and in the long term he believes Go’s cryptographic modules will mature and get better. But in the meantime, “we swapped out Go’s native crypto for OpenSSL,” he said, using assembly language versions of the C libraries.