I like Bolt too. It was my first choice :). Using it for read-only partitions sounds like a great idea. I think the current implementation looks like a tree if

I like Bolt too. It was my first choice :). Using it for read-only partitions sounds like a great idea. I think the current implementation looks like a tree if you "squint" a bit. There's a hierarchy of metrics and sources, and the arrays of points are like the leaf nodes. You're very correct about B+trees being efficient with sequential reads. We use MySQL with InnoDB for all of our time series where I work[0]. I started this way just to get a good understanding of what works and what doesn't. I think I'm on track to implementing something like a B+tree by using smaller extents of points. [0] http://www.slideshare.net/vividcortex/vividcortex-building-a-timeseries-database-in-mysql http://www.slideshare.net/vividcortex/vividcortex-building-a...