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DNSimple uses binary-level changes to reduce Erlang DNS server CPU costs

blog.dnsimple.com 19 min read Editor score 7/10

The post examines making DNS library operations cheaper in an Erlang origin server that handles queries missed by a global anycast cache. Per-query efficiency matters when optimizing high-volume network services.

What
DNSimple rewrote hot paths in dns_erlang, the DNS library used by its Erlang authoritative name servers.
How
On a production-shaped workload, the changes cut CPU per query by 12% and raised throughput before saturation by 14%.
Why it matters
Cheaper parsing and encoding can help systems serving high query volumes handle more traffic with the same CPU.
cache miss query decode/encode cache edge origin erldns dns_erlang
DNS queries pass from the cache edge to the origin and through erldns and dns_erlang. Sketched from the article's own text.

Read on blog.dnsimple.com → Lobsters · 4 comments

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