Excessive Storage DRS tasks on vCenter Server 6.0 U3 or later

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:
After upgrading to vCenter Server 6.0 Update 3 and later, you see these symptoms:

• Extremely aggressive SDRS svmotions.
• Deploying and cloning virtual machines from a template fails when SDRS is enabled on the cluster.
• StorageResourceManager.RecommendDatastores timeouts.
• You see the error:
  
  internal error 1009, java.net.SocketTimeoutException

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vCenter Server 6.0.x

Cause

This issue occurs due to the following:

• SDRS checks datastore usage every 10 min and if an overloaded datastore is identified, a load balance session will be scheduled in 10 min no matter if there is already a scheduled one or not. Since storage vMotion is time-consuming, LB sessions can pile up easily.
• Some tasks may get stuck leading many of them to pile up.

Resolution

This issue is resolved in vCenter Server 6.0 U3g, 6.5 U2 and 6.7 releases, available at VMware Patch Downloads