The other day when I was building a vSphere 6.0 environment up in my lab for testing I ran into an issue where performance was extremely slow in the web client and I was continually receiving an error that the VMware-dataservice-sca and vsphere-client status would change from green to yellow.  When I deployed the VCSA/PSC appliance I choose “Tiny” as the size option.  Even though my implementation is going to be under the 10 hosts and 100 VMs, I think this build was just not enough, and performance in the web client was just really lacking.  Searching the VMware KB I came across 2144950.  I found out this is a known issue affecting vCenter Server 6.0.  Here are the steps that I used to work around the error and gain performance back in the web client.

First I added additional RAM to the appliance.  Pretty straight forward, no magic there.  Then I used SSH to connect to the appliance and ran the follow command:

cloudvm-ram-size -C XXX vsphere-client

Replace the XXX with the size in MB that you want to increase the heap size.

If you are running a Windows  vCenter Server, find C:\ProgramFiles\VMware\vCenter Server\visl-integration\usr\sbin\cloudvm-ram-size.bat and run this command:

cloudvm-ram-size.bat -C XXX vspherewebclientsvc

Again swap out the XXX with the size in MB that you want to increase the heap size. Don’t forget to restart the vSphere client service.