Superfetch, What is it and How to disable it in Windows 10
Don’t let this Windows service negatively affect your computer’s performance.
Windows 10 is a definite improvement over previous versions in many ways, but it can also feel slow and lazy when it’s not configured properly. Of the many ways to improve Windows 10 performance, there is one lesser-known feature you should know about: Superfetch.
In this article, you will learn everything you need to know about what Superfetch is, how it works, why it could be problematic, and how to disable it if it is causing problems.
What is Superfetch?
Superfetch is a feature that was introduced in Windows Vista. The official description of the Superfetch service says that it “maintains and improves system performance over time,” but that’s vague and doesn’t tell the whole story.
Superfetch appears as “Host Service”: Superfetch “in Windows Task Manager. It sits quietly in the background, constantly analyzing RAM usage patterns and learning what kinds of applications run most often. Over time, Superfetch marks these applications as “frequently used” and preloads them into RAM in advance.
The idea is that when you want to run the application, it will launch much faster because it is already preloaded in memory.
By default, Superfetch is designed to occupy all available RAM space with preloaded applications. Don’t worry: it only takes care of unused memory. As soon as your system needs more RAM (for example, to load an application that has not been preloaded), it will give up the necessary memory.
Note that Superfetch is not the same as Prefetch, which is the preload memory manager that was introduced in Windows XP. Superfetch is actually the successor to Prefetch. What is the difference? Prefetch did not analyze usage patterns over time and adjusted its preload parameters accordingly.
Is Superfetch necessary?
For the most part, Superfetch is useful. If you have a modern PC with average specs or better, chances are that Superfetch works so well that you will never notice it. It’s very likely that Superfetch is already working on your system at this point and you haven’t even noticed it.
But there are some “problems” that can arise with Superfetch:
- Since Superfetch is always running in the background, the Superfetch service itself is always using some CPU and RAM.
- Superfetch does not eliminate the need to load applications into RAM. Rather, it relocates the load to an earlier time. Whenever that load occurs, your system continues to experience the same slowdown as if you were launching the application without Superfetch.
- System startup can be slow because Superfetch is preloading a lot of data from your hard drive to RAM. If your hard drive works 100% for a few minutes every time you start or restart your computer, Superfetch could be the culprit.
- The performance gains from Superfetch may be unnoticeable when Windows 10 is installed on an SSD drive. Since SSDs are so fast, you don’t need to preload them. If this interests you, check out our guide to moving Windows from hard drive to SSDs.
Superfetch is also known to cause performance issues during gaming, especially on systems that have 4GB of RAM or less. It’s unclear why this happens as it doesn’t happen for everyone, but we suspect it has to do with RAM-intensive games constantly requesting and freeing up memory, which can cause Superfetch to constantly load and unload data.
Is it safe to disable Superfetch? Yes. There is no risk of side effects if you decide to disable it. Our recommendation is that if your system works well, leave it on. If you have issues with hard drive usage, RAM usage, or degraded performance during RAM activities, then try turning it off and see if it helps. If it does, keep it off. If not, turn it back on.
To increase performance on a low RAM system, we recommend adjusting the Windows virtual memory limit and adjusting the Windows visual effects.