I was doing a health check for a customer and ran across the following warning event which occurred almost daily:

Event ID: 5206
Event Description: In memory container (hash table System.Health.EntityStateChangeData) had to drop data because it reached max limit. Possible data loss.

I did some research and found that the default for this container is 1024.  This can be configured through the following DWORD value:

HKLM\System\CurrentControlSet\Services\HealthService\Parameters:”State Queue Items”

I recommended that my customer set this to 2048 and if the errors continue to recur then try doubling it again.  There my be some other underlying issues that cause this queue to fill up so this my need to be troubleshot further if errors continue after this value has been raised significantly.