Huge MongoDB 3.4.9 Performance Improvements

Atlas just upgraded our db to 3.4.9 from 3.4.7 and… woah. We got like 10x query/update response time improvements across the board. Anyone else seeing this?

Still running 3.2.X, what had you wanting to use 3.4? Anything in particular you had to do to make it work with Meteor?

I think meteor works automatically if the DB you’re using runs 3.4

We didn’t make any particular choice to use 3.4; that’s just the version that hosted Atlas runs on.

Edit: Looks like we did fork the npm-mongo Meteor package and bump the version of the mongodb NPM package. Not sure if that’s necessary though.

There is an option when you create your cluster to specify the Mongo version. I explicitly chose 3.2 to be most compatible with Meteor but it sounds like 3.4 also works fine.

I highly recommend trying out 3.4.9; the performance improvements were totally insane. You can pretty easily see when the db upgrade happened…


That’s a huge improvement alright. Nothing really jumps out in the changelog except the optimisation of the large $in queries. Is that the case with your app ?

That was my best guess as well, since we do have some large $in queries. However, the perf increase was huge and before the update our CPU and men usage weren’t particularly high. There was also a mention of locking related to replica sets. Seems plausible that could be a source of improvement, especially for meteor apps.

I’m very interested in seeing if anyone else experiences benefits.

The release notes from MDG a few weeks ago indicated this would be the case. Good for you man!

I can’t wait to do the upgrade, but, am waiting until packages have been tested a little bit more. :slight_smile: