How to Avoid Activity Monitor Hurting Your SQL Server’s Performance

There is no question that monitoring the performance of your SQL Server deployment is an important part of any DBA’s maintenance and troubleshooting responsibilities.

However, the integrated tool provided by Microsoft to achieve this, unambiguously known as Activity Monitor, could actually be the culprit in causing performance dips.

Here is a look at why this happens and what you can do to deal with the issue of Activity Monitor interfering with the smooth running of an SQL Server database.

The basic dilemma

While Activity Monitor is undoubtedly useful in theory, in practice it can slow down server responsiveness in certain scenarios.

The reason for this is that the tool itself is a bit of a resource hog, so while it is running it will be monopolizing CPU clock cycles and a portion of the allocated memory which might otherwise be harnessed for processing queries and dealing with other transactions.

This additional overhead comes down to Activity Monitor running 13 queries repeatedly on a 10-second loop to keep the dashboard populated with stats you need to track performance. In particular, this can compromise things like TempDB, although it is also more generally responsible for suboptimal server operation, in contravention of its very purpose.

The simplest solution

Arguably the easiest way around this issue is to move away from the integrated Activity Monitor and instead endow your SQL Server setup with a third-party package that can monitor and diagnose the entire database.

Aside from overcoming the limitations of Activity Monitor, turning to the better-optimized tools from respected brands will also allow you to automate many of the main processes involved in overseeing SQL Server.

As such, DBAs will find that they have more time for other tasks, and can also benefit from things like alerts and notifications which draw their attention to issues that require troubleshooting.

The best tools will even be able to help with things like query optimization, security monitoring, and much more besides.

It may seem like more of a pain to bolt on a separate monitoring tool when SQL Server has its own functionality in this area, but the performance improvements and optimization potential of taking this route will easily justify any initial hassle involved.

The other advantages

Where Activity Monitor falls short, apart from in terms of its resource usage in SQL Server, is in the way that it presents data to DBAs.

It may be suited to giving you a snapshot of server performance and activity from moment to moment, but this is not always especially useful if you are hoping to fix broader conundrums with how a database operates.

Adding a separate monitoring tool to the mix will enable you to track performance over time, compare historic data to the current state of play and draw insights from having a fuller picture.

Final thoughts

If you have been skeptical about the benefits of having a standalone monitoring solution for SQL Server, hopefully, your concerns have been addressed by now.

You don’t have to completely ditch Activity Monitor, but just knowing about its downsides will let you manage your use of it more effectively.