OpenTSDB vs VelocityDB: What are the differences?
Developers describe OpenTSDB as "A scalable time series database". It is a distributed, scalable time series database to store, index & serve metrics collected from computer systems at a large scale. It can store and serve massive amounts of time series data without losing granularity. On the other hand, VelocityDB is detailed as "A NoSQL Object Database, extended as Graph Database is VelocityGraph". It is a C# .NET NoSQL Object Database that can be Embedded/Distributed, extended as Graph Database is VelocityGraph. It supports both embedded and distributed deployments.
OpenTSDB and VelocityDB can be categorized as "Databases" tools.
OpenTSDB is an open source tool with 3.84K GitHub stars and 1.13K GitHub forks. Here's a link to OpenTSDB's open source repository on GitHub.