- Scylla is a Cassandra compatible database written in C++
We also spent a large amount of time tuning the JVM’s garbage collector and heap settings, because GC pauses would cause significant latency spikes.
Although ScyllaDB is most definitely not void of issues, it is void of a garbage collector, since it’s written in C++ rather than Java. Historically, our team has had many issues with the garbage collector on Cassandra, from GC pauses affecting latency, all the way to super long consecutive GC pauses that got so bad that an operator would have to manually reboot and babysit the node in question back to health. These issues were a huge source of on-call toil, and the root of many stability issues within our messages cluster.
https://discord.com/blog/how-discord-stores-trillions-of-messages
https://www.scylladb.com/2019/12/12/how-scylla-scaled-to-one-billion-rows-a-second/