Thread Pool (TP) metrics

Thread Pool metrics reference grouped by similar subjects. Thread Pool metrics are prefixed with TP.

View thread pool stats in the Thread Pool Stats pane within the Node Details dialog.

Alerts and dashboard graphs can be set up for thread pool metrics in OpsCenter Monitoring.

Thread Pools are also monitored in the OpsCenter Performance Service. Refer to the Thread Pool Statistics for more information.

To view a list of keys that correspond to thread pool metrics collected by OpsCenter, refer to the Thread Pool Metrics Keys in the OpsCenter API documentation.

Thread Pool Stats can also be viewed by using the nodetool tpstats command. For more information, see Thread pool and read/write latency statistics.

Authentication

  • TP: Authentication Active

    Authentication Active

  • TP: Authentication Completed

    Authentication Completed

Authorization

  • TP: Authorization Active

    Authorization Active

  • TP: Authorization Completed

    Authorization Completed

Auth-z stage

  • TP: Auth Stage Active

    Auth Stage Active

  • TP: Auth Stage Pending

    Auth Stage Pending

  • TP: Auth Stage Completed

    Auth Stage Completed

Background IO Stages

  • TP: Background IO Stage Active

    Background IO Stage Active

  • TP: Background IO Stage Pending

    Background IO Stage Pending

  • TP: Background IO Stage Completed

    Background IO Stage Completed

Backpressure (Network)

  • TP: Network Backpressure Active

    Network Backpressure Active

  • TP: Network Backpressure Pending

    Network Backpressure Pending

  • TP: Network Backpressure Completed

    Network Backpressure Completed

  • TP: Network Backpressure Total Blocked

    Total Network Backpressure Blocked

Batches

Metrics for batch remove, batch replay, batch store, and batch store response.

  • TP: Batch Remove Active

    Batch Remove Active

  • TP: Batch Remove Pending

    Batch Remove Pending

  • TP: Batch Remove Completed

    Batch Remove Completed

  • TP: Batch Remove Total Blocked

    Total Batch

  • TP: Batch Replay Active

    Batch Replay Active

  • TP: Batch Replay Completed

    Batch Replay Completed

  • TP: Batch Store Active

    Batch Store Active

  • TP: Batch Store Pending

    Batch Store Pending

  • TP: Batch Store Completed

    Batch Store Completed

  • TP: Batch Store Total Blocked

    Total Batch Store Blocked

  • TP: Batch Store Response Active

    Batch Store Response Active

  • TP: Batch Store Response Completed

    Batch Store Response Completed

Cache Cleaning

  • TP: Cache Cleaning Pending

    Tasks pending to clean row caches during a cleanup compaction.

  • TP: Cache Cleaning Active

    Tasks to clean row caches during a cleanup compaction.

  • TP: Cache Cleaning Completed

    Tasks to clean row caches during a cleanup compaction.

Commit Log (Write Await)

  • TP: Write Await Commitlog Segment Active

    Write Await Commitlog Segment Active

  • TP: Write Await Commitlog Sync Active

    Write Await Commitlog Sync Active

  • TP: Write Await Commitlog Segment Completed

    Write Await Commitlog Segment Completed

  • TP: Write Await Commitlog Sync Completed

    Write Await Commitlog Sync Completed

Compaction Executor

  • TP: Compaction Executor Pending

    Pending compactions that are known. This metric could deviate from "pending compactions," which includes an estimate of tasks that these pending tasks might create after completion.

  • TP: Compaction Executor Active

    Active compactions that are known.

  • TP: Compaction Executor Completed

    Completed compactions.

Counter Acquire Lock

  • TP: Counter Acquire Lock Active

    Counter Acquire Lock Active

  • TP: Counter Acquire Lock Completed

    Counter Acquire Lock Completed

Execute Statements

  • TP: Execute Statement Active

    Execute Statement Active

  • TP: Execute Statement Completed

    Execute Statement Completed

Flushes (memtables)

  • TP: Flushes Pending

    Number of memtables queued for the flush process. A flush sorts and writes the memtables to disk.

  • TP: Post Flushes Pending

    Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.

  • TP: Flushes Active

    Up to memtable_flush_writers concurrent tasks to flush and write the memtables to disk.

  • TP: Post Flushes Active

    Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.

  • TP: Flushes Completed

    Number of memtables flushed to disk since the nodes start.

  • TP: Post Flushes Completed

    Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.

Frame Decode

  • TP: Frame Decode Active

    Frame Decode Active

  • TP: Frame Decode Completed

    Frame Decode Completed

Gossip

  • TP: Gossip Tasks Pending

    Number of gossip messages and acknowledgments queued and waiting to be sent or received.

  • TP: Gossip Tasks Active

    Number of gossip messages and acknowledgments actively being sent or received.

  • TP: Gossip Tasks Completed

    Number of gossip messages and acknowledgments recently sent or received.

Hint Dispatch (TPC) and Hint Dispatcher (regular TP)

  • TP: Hint Dispatch Active

    Hint Dispatch Active

  • TP: Hint Dispatch Pending

    Hint Dispatch Pending

  • TP: Hint Dispatch Completed

    Hint Dispatch Completed

  • TP: Hint Dispatch Total Blocked

    Total Hint Dispatch Blocked

  • TP: Hint Dispatcher Active

    Up to max_hints_delivery_threads tasks, each dispatching all hinted handoffs to a host.

  • TP: Hint Dispatcher Pending

    Pending tasks to send the stored hinted handoffs to a host.

  • TP: Hint Dispatcher Completed

    Number of tasks to transfer hints to a host that have completed.

Hint Response

  • TP: Hint Response Active

    Hint Response Active

  • TP: Hint Response Completed

    Hint Response Completed

Locks

  • TP: Counter Acquire Lock Active

    Counter Acquire Lock Active

  • TP: Counter Acquire Lock Completed

    Counter Acquire Lock Completed

LWT (lightweight transactions)

LWT metrics for propose, prepare, and commit. For more information, see Using lightweight transactions.

  • TP: Lwt Propose Pending

    Lwt Propose Pending

  • TP: Lwt Propose Active

    Lwt Propose Active

  • TP: Lwt Propose Completed

    Lwt Propose Completed

  • TP: Lwt Prepare Active

    Lwt Prepare Active

  • TP: Lwt Prepare Pending

    Lwt Prepare Pending

  • TP: Lwt Prepare Completed

    Lwt Prepare Completed

  • TP: Lwt Commit Pending

    Lwt Commit Pending

  • TP: Lwt Commit Active

    Lwt Commit Active

  • TP: Lwt Commit Completed

    Lwt Commit Completed

  • TP: Lwt Commit Total Blocked

    Total Lwt Commit Blocked

Memtable memory reclaims

The Memtable-reclaim-memory stats are available within the Thread Pool Stats pane of the Node details dialog.

  • TP: Memtable Reclaims Active

    Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.

  • TP: Memtable Reclaims Pending

    Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.

  • TP: Memtable Reclaims Completed

    Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.

Migrations

  • TP: Migrations Pending

    Number of pending tasks from system methods that modified the schema.

  • TP: Migrations Active

    Number of active tasks from system methods that modified the schema.

  • TP: Migrations Completed

    Number of completed tasks from system methods that modified the schema.

NodeSync Validation

  • TP: NodeSync Validation Active

    NodeSync Validation Active

  • TP: NodeSync Validation Completed

    NodeSync Validation Completed

Reads

  • TP: Read Disk Async Active

    Read Disk Async Active

  • TP: Read Disk Async Completed

    Read Disk Async Completed

  • TP: Read Secondary Index Active

    Read Secondary Index Active

  • TP: Read Secondary Index Completed

    Read Secondary Index Completed

Read Range NodeSync

  • TP: Read Range NodeSync Active

    Read Range NodeSync Active

  • TP: Read Range NodeSync Pending

    Read Range NodeSync Pending

  • TP: Read Range NodeSync Completed

    Read Range NodeSync Completed

  • TP: Read Range NodeSync Total Blocked

    Total Read Range NodeSync Blocked

Writes

  • TP: Write Switch For Memtable Active

    Write Switch For Memtable Active

  • TP: Write Switch For Memtable Completed

    Write Switch For Memtable Completed

Timed Timeout and Timed Unknown

  • TP: Timed Timeout Active

    Timed Timeout Active

  • TP: Timed Timeout Completed

    Timed Timeout Completed

  • TP: Timed Unknown Active

    Timed Unknown Active

  • TP: Timed Unknown Completed

    Timed Unknown Completed

Truncate

  • TP: Truncate Active

    Truncate Active

  • TP: Truncate Completed

    Truncate Completed

Unknown

Unknown thread pool metrics monitor threads for undetermined processes.

  • TP: Unknown Active

    Unknown Active

  • TP: Unknown Completed

    Unknown Completed

View Build Executor

  • TP: View Build Executor Active

    View Build Executor Active

  • TP: View Build Executor Pending

    View Build Executor Pending

  • TP: View Build Executor Completed

    View Build Executor Completed

Write Await Commit Log Segment and Sync

  • TP: Write Await Commitlog Segment Active

    Write Await Commitlog Segment Active

  • TP: Write Await Commitlog Segment Completed

    Write Await Commitlog Segment Completed

  • TP: Write Await Commitlog Sync Active

    Write Await Commitlog Sync Active

  • TP: Write Await Commitlog Sync Completed

    Write Await Commitlog Sync Completed

Write Defragment

  • TP: Write Defragment Active

    Write Defragment Active

  • TP: Write Defragment Pending

    Write Defragment Pending

  • TP: Write Defragment Completed

    Write Defragment Completed

  • TP: Write Defragment Total Blocked

    Total Write Defragment Blocked

Write Internal

  • TP: Write Internal Active

    Write Internal Active

  • TP: Write Internal Completed

    Write Internal Completed

Write Local

  • TP: Write Local Active

    Write Local Active

  • TP: Write Local Pending

    Write Local Pending

  • TP: Write Local Completed

    Write Local Completed

  • TP: Write Local Total Blocked

    Total Write Local Blocked

Write Remote

  • TP: Write Remote Active

    Write Remote Active

  • TP: Write Remote Pending

    Write Remote Pending

  • TP: Write Remote Completed

    Write Remote Completed

  • TP: Write Remote Total Blocked

    Total Write Remote Blocked

  • TP: Write Switch For Memtable Active

    Write Switch For Memtable Active

Write Switch (Memtables, Response)

  • TP: Write Switch For Memtable Active

    Write Switch For Memtable Active

  • TP: Write Switch For Memtable Completed

    Write Switch For Memtable Completed

  • TP: Write Switch For Response Active

    Write Switch For Response Active

  • TP: Write Switch For Response Completed

    Write Switch For Response Completed