Our index servers are showing less than 20% CPU utilization on admin console. When I actually ssh into the server and look at the CPU usage, it is actually using 100%+.
Admin console shows: 16.7 CPU utilization %
top command shows: 104.5% CPU usage for indexer process.
How many number of cores you allocated to indexer service?
You can check this in the setting tab in admin UI. Default number is 4, which means 4 core will be allocated to indexer service.
top commands shows that indexer is using 1 core.
Indexer calculates utilization based on number of core used / number of cores allocated.