Windows 11 was plagued by performance issues inherent to SSDs since last summer, when it was still only available to Insider program members. Unfortunately, the situation was not resolved with the launch version of the new operating system, released in early October 2021. Finally, after several months, it appears that the bug has been permanently eliminated thanks to the KB5008353 update released last week.

Prior to the arrival of this update, the speed of PC fixed storage devices could be severely impacted in Windows 11. Microsoft's release notes state that the update specifically addresses “a performance regression issue that occurs when activate the update sequence number (USN) journal ".
Windows Latest colleagues say that multiple users in forums and on Microsoft's official Feedback Hub have said that Windows 11 storage devices have finally returned to the performance recorded in Windows 10. The comments appear to cover a wide range of drives, from those which use the SATA interface to the latest M.2 NVMe SSDs. Apparently, Microsoft took a long time to find the cause of this problem, which already last December was reported as resolved with the Preview Update KB5007262. At the time we reported that the patch provided much improved random write speeds, but it appears to have only worked on a subset of configurations.

If you have recently migrated to Windows 11, or have a pre-built system with Windows 11 whose disk performance does not seem to be up to par, we recommend that you update the operating system as soon as possible and verify that the update KB5008353 is installed. This late January update contains a very long list of useful improvements and fixes, covering a wide range of issues affecting Bluetooth devices, app icons, crashes with multi-display mode, and much more.