https://www.infoq.com/news/2018/09/logdevice-distributed-logstorage
About how FB uses it and the design features it was made to support (quoting):
"Facebook open sourced their internal distributed log storage project called LogDevice. It offers high write availability using replication, durable log storage and recovery from failure.
Most of Facebook's applications that perform logging require high write availability, durable storage of logs, and workloads that vary in terms of performance and latency requirements. Another important requirement was to be able to survive hardware failures. An older Facebook project called Scribe was more focused on aggregating logs to central storage, and there were cases where data loss could occur. Scribe now uses LogDevice as a log storage backend.
Facebook uses LogDevice internally in its datacenters for stream processing pipelines, distribution of database index updates, machine learning pipelines, replication pipelines, and durable task queues where it ingests over 1TB/sec of data. Although Facebook has built a lot of open source tools to manage LogDevice clusters, they are yet to open source any of those except a basic toolset at this point. The LDShell tool allows cluster management from the command line, and the complementary LDQuery command can be used to view cluster statistics."
(...) "[Other] log storage systems [include] Apache BookKeeper and Apache Kafka.
