How and why the leap second affected Cloudflare DNS
January 01, 2017 10:40PM
At midnight UTC on New Year’s Day, deep inside Cloudflare’s custom RRDNS software, a number went negative when it should always have been, at worst, zero. A little later this negative value caused RRDNS to panic....
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Economical With The Truth: Making DNSSEC Answers Cheap
June 24, 2016 5:31PM
We launched DNSSEC late last year and are already signing 56.9 billion DNS record sets per day. At this scale, we care a great deal about compute cost....
Go coverage with external tests
January 19, 2016 6:19PM
The Go test coverage implementation is quite ingenious: when asked to, the Go compiler will preprocess the source so that when each code portion is executed a bit is set in a coverage bitmap....
Creative foot-shooting with Go RWMutex
October 29, 2015 9:26PM
Hi, I'm Filippo and today I managed to surprise myself! (And not in a good way.)
I'm developing a new module ("filter" as we call them) for RRDNS, CloudFlare's Go DNS server....
DNS parser, meet Go fuzzer
August 06, 2015 2:40PM
Here at CloudFlare we are heavy users of the github.com/miekg/dns Go DNS library and we make sure to contribute to its development as much as possible. Therefore when Dmitry Vyukov published go-fuzz and started to uncover tens of bugs in the Go standard library, our task was clear....
August 03, 2015 12:26PM
Quick and dirty annotations for Go stack traces
CloudFlare’s DNS server, RRDNS, is entirely written in Go and typically runs tens of thousands goroutines. Since goroutines are cheap and Go I/O is blocking we run one goroutine per file descriptor we listen on and queue new packets for processing....