Microsoft has introduced a new Microsoft Defender feature called “performance mode” for developers in Windows 11, designed to reduce the impact of virus scans when scanning files stored on Dev Drives.

Featured at this year’s Microsoft Build conference, Dev Drive is a new Windows 11 storage volume type using Resilient File System (ReFS) available in public preview and provides developers with improved performance and resilience against file corruption. data.

These developer-focused storage volumes are designed to store large datasets, such as source code repositories, output or build staging files, and package caches (e.g. Npm, Nuget).

As Panos Panay, Director of Windows and Devices Products at Microsoft stated, the combination of Dev Drive and Defender performance modes can result in a build speed increase of up to 30%.

“Dev Drive is based on the Resilient File System, which combined with a new Performance Mode feature in Microsoft Defender for Antivirus, delivers up to 30% improvement in file system build times for scenarios file I/O,” Panay said. said.

“The new performance mode is more secure for your workloads than folder or process exclusions, providing the ultimate solution for balancing security and performance.”

When this new Defender Antivirus mode is enabled, it balances performance and threat protection by delaying scans until file operations are complete.

To set up a new development drive, you need to click on the “Create Development Drive” button after going to System > Storage > Advanced Store Settings > Disks and Volumes in the Windows Settings app.

Performance mode will be enabled by default for “trusted” drives, which is true for all newly created development drives, and will only be available if real-time protection is enabled.

It is also ONLY available for development drives and cannot be activated on volumes using other file systems, such as FAT32 or NTFS.

“A Dev Drive is automatically designated as Trusted, providing the best possible performance by default. A Trusted Dev Drive means that the developer using the volume has a high degree of confidence in the security of the content stored on it,” Microsoft explain.

However, any development player transferred from another device will be marked as untrusted and will instead use Microsoft Defender’s real-time protection mode, not the new performance mode.

Nevertheless, it is possible to set a development drive as trusted using the FSUTIL command line utility, which will automatically enable the new performance mode feature.

Currently, Dev Drives are only available to Insiders in the Windows 11 Dev Channel and require a minimum of 8 GB of RAM and at least 50 GB of free disk space.

Performance Drive also requires Microsoft Defender Antivirus, Microsoft Defender for Business, or Microsoft Defender for Endpoint Plan 1 or Plan 2 with Antimalware Platform Build 4.18.2303.8 (or later) and Antimalware Signature Build 1.385.1455.0 ( or later).