Two Weeks Later: Finding and Eliminating Long Tail Latencies

A little over two weeks ago, we shared extensive benchmarking results of edge networks all around the world.  It showed that on a range of tests (TCP connection time, time to first byte, time to last byte), and on a range of measurements (p95, mean), that Cloudflare had some impressive network performance. But we weren't the fastest everywhere. So we made a commitment: we would improve in at least 10% of networks where we were not #1.

Today, we’re happy to tell you that we’ve delivered as promised. Of the networks where our average latency exceeded 100ms behind the leading provider during Speed Week, we’ve dramatically improved our performance. There were 61 networks; now, we’re the fastest in 29 of them. Of course, we’re not done yet — but we wanted to share with you the latest results, and explain how we did it.

Measuring What Matters

In the process of quantifying network performance, it became clear where we were not the fastest everywhere. There were 61 country/network pairs where we more than 100ms behind the leading provider:

Once that was done, the fun began: we needed to go through the process of figuring out why we were slow — Continue reading