Too Much NUMA

Denny Cherry discusses the performance downsides of having too many NUMA nodes on a server:

At one client I was working with in 2015 they had a server which was configured very similarly to what I’ve described above. They had 32 cores, with 11 NUMA nodes. One NUMA node has 4 cores, the next 9 had three cores each, while the 11th NUMA node had one core in it.

When monitoring the performance on the server what we saw was that three cores were running at 100% (or close to it) while the other cores were running at about 4%.

The reason for this, is that SQL Server is NUMA aware, and it was trying to get the best performance possible out of the configuration that it had access to.

Moderation in everything.  Also, it’s important to plan growth and check every once in a while for oddities like this.

Related Posts

Alerting In Azure SQL Database

Arun Sirpal shows how to set up an alert for an Azure SQL Database: I keep things simple and like to look at certain performance based metrics but before talking about what metrics are available let’s step through an example. For this post I want to setup an alert for CPU percentage utilised that when […]

Read More

Validating Database Mail

Frank Gill has a script to validate that your database mail settings are valid: In my last post, I shared a script to automate the migration of SQL Server Database Mail settings. In this post, I show how to send test e-mails from all Database Mail profiles on an instance. The migration I was working […]

Read More


June 2016
« May Jul »