Impacted performance over NDB/NSBSSL

Products

• VMware vSphere ESXi

Issue/Introduction

You are experiencing slow replication and restore over NDB, and may observe the backup job takes more time when vSphere is upgraded to 7.0 and later.

Environment

• VMware vSphere ESXi 7.0.2

Cause

NBD is a transport mode of VDDK while VDDK (Virtual Disk Development Kit) is an SDK to develop backup application. It is a backup application can use NBD mode of VDDK to transfer VM disk data and backup the VM.

Resolution

VMware Engineering are aware of this issue, it is currently under investigation. Please subscribe to this KB to get notified on changes and updates.

Workaround: We have some improvements noted in Backup speed is slow over NBD transport mode for VMs on high-latency storage.

Additional Information

VMware Engineering has identified the issue only happens for Windows proxy. We have improved the performance for Windows with VDDK 8.0 and VDDK 7.0.3 Patch 2.