简介
GET _cat/thread_pool 指令可以展示 ES 自运行以来的线程池统计信息。有些信息是实时的（如active），有些信息是累计的（例如 rejected）。
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示例
示例1：默认输出
运行：
GET _cat/thread_pool
输出：
Myhost analyze 0 0 0
Myhost ccr 0 0 0
Myhost data_frame_indexing 0 0 0
Myhost fetch_shard_started 0 0 0
Myhost fetch_shard_store 0 0 0
Myhost flush 0 0 0
Myhost force_merge 0 0 0
Myhost generic 0 0 0
Myhost get 0 0 0
Myhost listener 0 0 0
Myhost management 1 0 0
Myhost ml_datafeed 0 0 0
Myhost ml_job_comms 0 0 0
Myhost ml_utility 0 0 0
Myhost refresh 0 0 0
Myhost rollup_indexing 0 0 0
Myhost search 0 0 0
Myhost search_throttled 0 0 0
Myhost security-token-key 0 0 0
Myhost snapshot 0 0 0
Myhost warmer 0 0 0
Myhost watcher 0 0 0
Myhost write 0 0 0
每一列依次是 node_name、name、active、queue、rejected 。
示例2：显示表头
执行：
GET _cat/thread_pool?v
输出：
node_name name active queue rejected
Myhost analyze 0 0 0
Myhost ccr 0 0 0
Myhost data_frame_indexing 0 0 0
Myhost fetch_shard_started 0 0 0
Myhost fetch_shard_store 0 0 0
Myhost flush 0 0 0
Myhost force_merge 0 0 0
Myhost generic 0 0 0
Myhost get 0 0 0
Myhost listener 0 0 0
Myhost management 1 0 0
Myhost ml_datafeed 0 0 0
Myhost ml_job_comms 0 0 0
Myhost ml_utility 0 0 0
Myhost refresh 0 0 0
Myhost rollup_indexing 0 0 0
Myhost search 0 0 0
Myhost search_throttled 0 0 0
Myhost security-token-key 0 0 0
Myhost snapshot 0 0 0
Myhost warmer 0 0 0
Myhost watcher 0 0 0
Myhost write 0 0 0
示例3：通过 h 指定展示的列
运行：
GET _cat/thread_pool?v&h=name,core,host,port
输出：
name core host port
analyze 127.0.0.1 9300
ccr 127.0.0.1 9300
data_frame_indexing 127.0.0.1 9300
fetch_shard_started 1 127.0.0.1 9300
fetch_shard_store 1 127.0.0.1 9300
flush 1 127.0.0.1 9300
force_merge 127.0.0.1 9300
generic 4 127.0.0.1 9300
get 127.0.0.1 9300
listener 127.0.0.1 9300
management 1 127.0.0.1 9300
ml_datafeed 1 127.0.0.1 9300
ml_job_comms 4 127.0.0.1 9300
ml_utility 1 127.0.0.1 9300
refresh 1 127.0.0.1 9300
rollup_indexing 127.0.0.1 9300
search 127.0.0.1 9300
search_throttled 127.0.0.1 9300
security-token-key 127.0.0.1 9300
snapshot 1 127.0.0.1 9300
warmer 1 127.0.0.1 9300
watcher 127.0.0.1 9300
write 127.0.0.1 9300
示例4：展示特定线程池的统计信息
例如 analyze 线程池。
运行：
GET _cat/thread_pool/analyze?v&h=name,core,host,port
输出：
name core host port
analyze 127.0.0.1 9300