Windows 10 Insider Build 18312 Increases FLS Limits In Windows 10:

Windows 10 Insider Build 18312 Increases FLS Limits In Windows 10

Microsoft has announced that Windows 10 Insider Build 18312 Increases FLS Limits In Windows 10. What does this mean for musicians and audio producers using Windows?

About FLS limits

Recently, there’s been some contention as to the number of plugins that can be instantiated in Windows 10 due to FLS (Fiber Local Storage) limits in the Operating System; these limits have been in place since Windows XP, and so this is nothing new. This was especially prevalent for users of Steinberg Cubase, who have taken issue with not being able to instantiate as many plugins as they’d like in their DAW (Digital Audio Workstation) via DLL files (Dynamic Link Libraries, or, the files that make up the plugins that we use every day in our DAW). The issue that users have run into is one in which the ability to load potentially thousands of those DLLs was hindered by FLS limits in Windows 10, which caused some users to want to roll back to using Windows 7 or Windows 8. As both of these Operating Systems are nearing the end of their usable life, and as Windows 10 offers many other benefits for pro audio production, power users have been chomping at the bit for increased FLS slot limits to allow more DLLs to be loaded in the process of audio production.

The good news is that this new build of Windows takes aim at that issue.

What Windows 10 Insider Build 18312 brings to the table to correct FLS limits 

From the Microsoft blog entry about Windows 10 Insider Build 18312: 

As PCs get more powerful, musicians have created increasingly complex projects with more tracks, more instruments, and deeper effects chains. As a result, some of those musicians were running up against a FLS (Fiber Local Storage) slot allocation ceiling that prevented them from loading into their DAWs (Digital Audio Workstations) as many unique plugins as they’d like. This build greatly raises that per-process FLS slot allocation ceiling, allowing loading potentially thousands of unique plugins. Beyond musicians, this change will positively impact any application that dynamically loads hundreds or thousands of unique DLLs that have statically-linked Visual C++ runtimes, or otherwise allocate FLS slots.


This is especially good news for those users of DAWs in which they were hitting a wall on the number of plugins which could be instantiated, by potentially allowing users to load thousands of plugins without hitting the FLS slot limit ceiling.

Does this affect my workflow? 

It stands to reason that many DAW users won’t see these benefits immediately, as the ability to instantiate a very large amount of plugins in a DAW such as Steinberg Cubase is still not an issue for many users. However, those power users, and those who wish to  push the limit of their DAW, will likely see a benefit from this insider build.

How do I get Windows 10 Insider Build 18312? 

As this is an insider build, it is not yet released for general public consumption. You can find more information about this build by clicking here. If you run a test partition or other sandboxed operating system on your PCAL pro audio PC, you could test this new build, or, you can wait for it to release to the public via Windows Update, but you’ll need to be a Windows insider in order to do so.

We do not yet know the official release date of this new build. Rest assured, we at PCAudiolabs will be testing this new build and looking for the benefits of increased FLS limits in Windows 10 for audio production.

As always, if you have questions, comments, or need a new pro audio PC, don’t hesitate to contact us today!