VoltDB 2.0 was released last week and I wanted to take this opportunity to summarize the important new features, including enhancements for database durability and recovery; key performance and interoperability improvements; and many enhancements geared at helping developers use VoltDB productively. Here are the details:

• Durability and recovery.  Version 2.0 introduces a new feature called Command Logging that allows VoltDB databases to be fully recoverable in the face of severe failures caused by hardware and software crashes.  Available in VoltDB Enterprise Edition, Command Logging ensures that every transaction applied to a VoltDB database is separately logged to disk.  Following a

… Read more

In the previous blog post (http://newblog.voltdb.com/intro-voltdb-command-logging), Ariel Weisberg described how VoltDB’s command logging feature works. He also briefly mentioned how we replay command logs during the recovery process. In this post, I am going to focus on the replay process and discuss how VoltDB recovers from catastrophic events.

Goals of Command Logging Replay

The goals of command logging replay are pretty simple:

1. Ensure that the recovered database is 100% accurate to the last usable transaction in the command log
2. Complete the recovery process in the shortest possible time

Command logging obviously adds important new functionality to VoltDB’s infrastructure.  … Read more

VoltDB’s new command logging feature reduces the window of data loss during a cluster wide failure from single digit minutes (the window between snapshots) to zero. Command logging can be tuned to give you the same amazing latency and throughput you get from VoltDB, even on a single 7.2k SATA disk. Our unique approach to log based durability exploits the determinism and replication inherent in VoltDB’s architecture to avoid the overhead and latency of ARIES style logging.

How We Log

A command log is kept at every node and contains partially ordered stored procedure invocations. As stored procedure invocations arrive … Read more

We, at VoltDB, are excited to tell you about the command logging feature that we’ve been working on this summer. We’ve built this feature because our customers asked for it, and they’ve given us some great feedback on how it should work. Here’s a heads up to get you thinking about how you can make use of this new functionality.

So what’s command logging and why are we so excited about it? First, let me remind you of VoltDB’s snapshot functionality. A database snapshot is exactly what it sounds like — a point-in-time copy of the database contents written to … Read more