# Thread Pool Related (Continue...)

+ `Grafana` Monitor TikV-Details —> Thread CPU —> Unified Read Pool CPU


![left](./student-guide/diagram/09-TiKV-Thread-CPU-02-01.png)
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- Thread pool related
  - Thread CPU - gRPC poll CPU: is responsible for processing all network request. It forwards request of different task types to different thread pools. The imbalance indicates that there may be hot issues.

  - Thread CPU - Unified read pool CPU: is a combination of the Coprocessor thread pool and the Storage Read Pool. All read request include kv get, kv batch get, raw kv get, coprocessor, etc. will all be executed in this thread pool.

  - Thread CPU - Scheduler Worker CPU: Responsible for detecting write transaction conflicts, converting request such as two-stage commit, pessimistic lock, transaction rollback, etc. of the transaction into an array of key-value pairs, and then hands it to the Raftstore thread for Raft log replication.

  - Thread CPU - Raft Store CPU: is responsible for processing all Raft messages and proposals to add new logs (Proposals), writing logs to disk, and sending the logs to the Apply thread when the logs are agreed upon in most replica.

  - Thread CPU - Async apply CPU: After receiving the committed log from the Raftstore thread pool, it is responsible for parse it into a key-value request, writing it to RocksDB, and calling a callback function to inform the gRPC thread pool that the write request has been completed and the result is return to the client.