During our launch last week we discussed the amazing benefits of XtremIO’s In-Memory Metadata architecture. Some have seen fit to FUD this approach as risky – what happens to valuable metadata if a controller (or power) fails and memory contents are lost? Believe it or not, we did think about these things when designing XtremIO.So let us clear the air – in-memory metadata is a run-time capability of the array that significantly boosts performance. Metadata is not exclusively kept in memory. It is also journaled, protected, and hardened to SSD and can tolerate any failure event in the array. We couldn’t cover every detail of this during a one-hour launch event, so here’s what we didn’t have time to say last week.

To set the foundation, let’s briefly review the concept of metadata. In the context of storage systems, metadata is simply useful internal information managed by the array…