Reduced performance when administering ESX hosts in vCenter Server
Normal management tasks take a long time to execute
Tasks appear to stop responding when trying to start or stop a virtual machine
Restarting the VMware Infrastructure/vSphere Client and vCenter Server does not help
This issue affects only a specific ESX host in vCenter Server
This issue may occur if the Service Console of the ESX host has less memory.
Virtual machine management is performed using the hostd management agent on the ESX host. In some cases, you may experience these symptoms if resources, in particular Service Console memory become limited on the ESX host.
To resolve this issue, check for excessive system swapping. Any swapping slows down hostd and other management processes.
To check for excessive swapping:
Log in as root to the ESX host with an SSH client.
This example output indicates that 512MB of memory is allocated to the Service Console and that 0MB of swap is being used. If your system indicates excessive swapping by showing a Swapused value which is almost the same as the Swaptotal and a low Swapfree value, it is most likely suffering from resource starvation. For more information, see Checking for resource starvation of the ESX Service Console (1003496).