Data transfer rate between the arrays can be slow when Hardware Accelerated Move (XCOPY) is enabled.

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:
While migrating data between two arrays using sVmotion with Hardware Accelerated Move (XCOPY) enabled user may see data transfer rate between the arrays is slow compared to when XCOPY is disabled.

The slowness depends on amount of data being migrated and connection between the arrays , however the time to migrate data for XCOPY enabled and disabled case differs.

Environment

VMware vSphere ESXi 7.0.x
VMware vSphere ESXi 8.0.x

Cause

This is an existing issue and caused by current design where ESXi assumes that XCOPY will be used when Hardware Accelerated Move (XCOPY) is enabled.

When XCOPY is enabled the data migration design assumes that hardware acceleration will be used which later impacts the performance when hardware acceleration is actually not used for data migration and migration falls back to software data migration.

This is applicable when when data is being migrated between arrays.

Resolution

Currently there is no resolution.

Workaround:
As work around customer can disable Hardware Accelerated Move (XCOPY) to improve the data migration performance.
To disable XCOPY on ESXi host please follow steps mentioned in KB - https://kb.vmware.com/s/article/2146567
 
Please note: Please disable XCOPY on all hosts that is involved in migration.