Microsoft has confirmed a new known issue causing customers to experience a significant performance hit when copying large files over SMB after installing the Windows 11 22H2 update.
“There is a performance reduction in 22H2 when copying larger files from a remote computer down to a Windows 11 computer or when copying files on a local drive,” explained Ned Pyle, Principal Program Manager in the Windows Server engineering group.
Microsoft has shared additional information regarding this issue in a support document detailing the contents of the KB5017389 preview cumulative update released a week ago.
“Copying large multiple gigabyte (GB) files might take longer than expected to finish on Windows 11, version 22H2,” Microsoft revealed.
“You are more likely to experience this issue copying files to Windows 11, version 22H2 from a network share via Server Message Block (SMB) but local file copy might also be affected.”
The company added that Windows devices used in home networks or small offices are less likely to be affected by this newly acknowledged issue.
Workaround available
Microsoft also shared a workaround for customers affected by this known issue after updating their devices to Windows 11 22H2.
As Redmond explains, impacted users can mitigate the file copying performance hit over SMB with the help of file copy tools that don’t use cache manager (buffered I/O).
