This is your weekly summary of Compose news for those changes and updates which can make your life easier. In this August 28th 2018 edition, we look at connection count issues with MongoDB. And we also take a browse through the past week's Compose Articles.
MongoDB Connection Counts
TL;DR: If you run MongoDB and Node with the official MongoDB Node driver, update your driver to version 3.1.3 or later.
Recently, we have seen customers with MongoDB have connection counts hitting the limits of their database deployment. A quick refresher on connection limits. Connections can be expensive depending on which database you are dealing with. The more connections you have, the more memory is consumed to handle those connections and the less memory you have to handle your database's working set of data.
That's why there are limits - to stop you eating all your memory on not-database operations. For example, on Compose PostgreSQL the connection limit starts off at 100 connections. Connections there take a fair chunk of memory so they need to be constrained. On MongoDB, connections are a lot lighter and we set the limit at 5000. That's across the database as a whole, not particular portals. So, with 5000 connections it should be pretty hard to hit the limit and if you do, chances are there's something up with your application.
Which is why it was interesting to see a number of Compose customers doing just that, hitting the 5000 connection limit very quickly. Our support team and developers looked into the issue and couldn't see any internal problem which would generate these problems. Customers assured us they were carefully pooling their connections which is a great way to avoid connection blowout. So we wondered if it was a widespread problem with a driver.
Then we were shown this ticket from the MongoDB Node driver, one of a number of issues regarding connection growth. It is one of a number of fixes in version 3.1.3 which was released on the 13th of August. We've now had reports that applying this version seems to eliminate the rapid connection growth issue that some users are experiencing.
So, if you are experiencing a connection blowout and you run MongoDB with the MongoDB Node driver, update your driver to version 3.1.4 - which just came out, and please, test your application again. We hope that this change will resolve the problem, but just drop a line to Compose Support if you experience anything similar.
Last week, we started the seven day cycle with Noteworthy news that MongoDB Classic was no longer provisionable on Compose.com. We then released Redli, a Redis client and caught up with the news.
- Redli is a new Redis client from Compose, designed to make it simpler than ever to connect to Redis when it's secured with TLS/SSL. It's open source and ready to go, so catch up with what it can do in this article.
- In NewsBits, we caught up with the latest Elasticsearch release, a controversial license change ruffling up the Redis community, the latest on FoundationDB, a Microsoft open source database called FASTER and another Struts vulnerability.
That's it for this week's Noteworthy at Compose. Onwards to next week!