Over the last couple of years, we have built and deployed a reliable publish-subscribe system called Wormhole. Wormhole has become a critical part of Facebook’s software infrastructure. At a high level, Wormhole propagates changes issued in one system to all systems that need to reflect those changes – within and across data centers.Facebook’s Kafka-alike, basically, although with some additional low-latency guarantees. FB appear to be using it for multi-region and multi-AZ replication. Proprietary.
Turns out gnuplot has a pretty readable ASCII terminal rendering mode; combined with ‘watch’ it makes for a nifty graphing one-liner