System performance may degrade when cluster capacity utilization exceeds 75% and vSAN ESA is configured with 10Gb networking.

Products

• VMware vSAN 8.x

Issue/Introduction

vSAN ESA performs routine background processes to reclaim storage for reuse. As the storage devices in the cluster become more full, there is a chance that this background process becomes less efficient and increases the load on the vSAN Network. When 10Gb is used for the vSAN ESA network, and the disk capacity usage becomes high, the resulting increase in
network utilization may degrade the maximum storage performance.

Environment

vSAN ESA

Cause

vSAN ESA is optimized for higher speed networks.

Limited network bandwidth for vSAN operations

Resolution

Consider using 25G network our higher when using vSAN ESA

When using a 10Gb network for vSAN ESA, be more conservative in managing cluster capacity. Do not let capacity (used + reserved) to exceed 75%.