Bulk queue size question

my setting in elasticsearch.yml about bulk thread pool is below:
threadpool.bulk.type: fixed
threadpool.bulk.size: 4
threadpool.bulk.queue_size: 10
threadpool.bulk.reject_policy: caller

but when server running and I checked it with /_cat/thread_pool?v, bulk.queue is over 100. dose I misunderstand the threadpool.bulk.queue_size setting?