Server-Side Copy

• Regular copy

• Client reads data from the server
• Client writes same data back to the server
• Disk and network round trip

• Server-side copy

• Client offloads the copy operation to the server
• Server reads data from disk, then writes back
• Disk round trip only

• Server-side copy SMBs

• FSCTL_SRV_COPYCHUNK
• FSCTL_SRV_REQUEST_RESUME_KEY (obtain source file identifier)
• FSCTL_OFFLOAD_READ / FSCTL_OFFLOAD_WRITE