RavenDB performance optimizations
Just to note, you’ll probably read this post about a month after the change was actually committed.
I spent the day working on a very simple task, reducing the number of writes that RavenDB makes when we perform a PUT operation. I managed to reduce one write operation from the process, but it took a lot of work.
I thought that I might show you what removing a single write operation means, so I built a simple test harness to give me consistent numbers (in the source, look for Raven.Performance).
Please note that the perf numbers are for vanilla RavenDB, with the default configuration, running in debug mode. We can do better than that, but what I am interested in is not absolute numbers, but the change in those numbers.
Here are the results for build 124, before the change:
Wrote 5,163 documents in 5,134ms: 1.01: docs/ms
Finished indexing in 8,032ms after last document write
And here are the numbers for build 126, after the change:
Wrote 5,163 documents in 2,559ms: 2.02: docs/ms
Finished indexing in 2,697ms after last document write
So we get double the speed at write time, but we also get much better indexing speed, this is sort of an accidental by product, because now we index documents based on range, rather than on specific key. But it is a very pleasant accident.