VM Shows High Disk Usage

Products

• VMware vSphere ESXi

Issue/Introduction

On occasion an administrator may notice that one or several VMs in their environment are performing poorly due to large numbers of Storage operations performed by the VM. This would be shown within the Monitor tab of your ESXi or vSphere web UI under Overview and with the view set to Disks. 

• Here is an example of a VM which is showing an unusually high amount of Disk read/write jobs causing the VM to perform poorly.
  • Note: Dates/Times within the graph shown below are arbitrary and will be different outside of this use-case:

 

Environment

VMware ESXi 

Cause

Guest-OS initiated read/write jobs that are causing the VM to show large amounts of Storage throughput. 

Resolution

VMware ESXi provides virtual resources to the VM (specified within the VM's .vmx file) and the Guest OS installed within that VM is the party responsible for managing those resources. If a VM is showing any unusual signs of behavior in regards to its resources (CPU, Memory, RAM, and/or Network usage) the issue needs to be first scoped within the Guest OS. Please review Guest-OS side performance data to confirm what Applications/Processes are taking up storage resources and if needed, engage your Guest OS vendor. 

If your Guest OS does not show any signs for cause in relation to the resource usage, please open a Support Request with Broadcom's Support team:

• https://knowledge.broadcom.com/external/article/142884/creating-and-managing-broadcom-support-c.html