Gnocchi 2.0 release

A little more than 3 months after our latest minor release, here is the new major version of Gnocchi, stamped 2.0.0. It contains a lot of new and exciting features, and I’d like to talk about some of them to celebrate!

You may notice that this release happens in the middle of the OpenStack release cycle. Indeed, Gnocchi does not follow that 6-months cycle, and we release whenever our code is ready. That forces us to have a more iterative approach, less disruptive for other projects and allow us to achieve a higher velocity. Applying the good old mantra release early, release often.

Documentation

This version features a large documentation update. Gnocchi is still the only OpenStack server project that implements a “no doc, no merge” policy, meaning any code must come with the documentation addition or change included in the patch. The full documentation is included in the source code and available online at gnocchi.xyz.

Data split & compression

I’ve already covered this change extensively in my last blog about timeseries compression. Long story short, Gnocchi now splits timeseries archives in small chunks that are compressed, increasing speed and decreasing data size.

Measures batching support

Gnocchi now supports batching, which allow submitting several measures for different metric in a single request. This is especially useful in the context where your application tends to cache metrics for a while and is able to send them in a batch. Usage is fully documented for the REST API.

Group by support in aggregation

One of the most demanded features was the ability to do measure aggregation no resource, using a group by type query. This is now possible using the new groupby parameter to aggregation queries.

Ceph backend optimization

We improved the Ceph back-end a lot. Mehdi Abaakouk wrote a new Python binding for Ceph, called Cradox, that is going to replace the current Python rados module in the subsequent Ceph releases. Gnocchi makes usage of this new module to speed things up, making the Ceph based driver really, really faster than before. We also implemented asynchronous data deletion, which improves performance a bit.

The next step will be to run some new benchmarks like I did a few months ago and compare with the Gnocchi 1.3 series. Stay tuned!