Thread Pool (TP) metrics

Thread Pool metrics reference for OpsCenter Monitoring.

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 [active-authentication]
Authentication Active
TP: Authentication Completed [completed-authentication]
Authentication Completed

Authorization

TP: Authorization Active [active-authorization]
Authorization Active
TP: Authorization Completed [completed-authorization]
Authorization Completed

Auth-z stage

TP: Auth Stage Active [active-auth-stage]
Auth Stage Active
TP: Auth Stage Pending [pending-auth-stage]
Auth Stage Pending
TP: Auth Stage Completed [completed-auth-stage]
Auth Stage Completed

Background IO Stages

TP: Background IO Stage Active [active-background-io-stage]
Background IO Stage Active
TP: Background IO Stage Pending [pending-background-io-stage]
Background IO Stage Pending
TP: Background IO Stage Completed [completed-background-io-stage]
Background IO Stage Completed

Backpressure (Network)

TP: Network Backpressure Active [active-network-backpressure]
Network Backpressure Active
TP: Network Backpressure Pending [pending-network-backpressure]
Network Backpressure Pending
TP: Network Backpressure Completed [completed-network-backpressure]
Network Backpressure Completed
TP: Network Backpressure Total Blocked [total-blocked-network-backpressure]
Total Network Backpressure Blocked

Batches

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

TP: Batch Remove Active [active-batch-remove]
Batch Remove Active
TP: Batch Remove Pending [pending-batch-remove]
Batch Remove Pending
TP: Batch Remove Completed [completed-batch-remove]
Batch Remove Completed
TP: Batch Remove Total Blocked [total-blocked-batch-remove]
Total Batch Remove Blocked
TP: Batch Replay Active [active-batch-replay]
Batch Replay Active
TP: Batch Replay Completed [completed-batch-replay]
Batch Replay Completed
TP: Batch Store Active [active-batch-store]
Batch Store Active
TP: Batch Store Pending [pending-batch-store]
Batch Store Pending
TP: Batch Store Completed [completed-batch-store]
Batch Store Completed
TP: Batch Store Total Blocked [total-blocked-batch-store]
Total Batch Store Blocked
TP: Batch Store Response Active [active-batch-store-response]
Batch Store Response Active
TP: Batch Store Response Completed [completed-batch-store-response]
Batch Store Response Completed

Cache Cleaning

TP: Cache Cleaning Pending [pending-cache-cleanup-stage]
Tasks pending to clean row caches during a cleanup compaction.
TP: Cache Cleaning Active [active-cache-cleanup-stage]
Tasks to clean row caches during a cleanup compaction.
TP: Cache Cleaning Completed [completed-cache-cleanup-stage]
Tasks to clean row caches during a cleanup compaction.

Commit Log (Write Await)

TP: Write Await Commitlog Segment Active [active-write-await-commitlog-segment]
Write Await Commitlog Segment Active
TP: Write Await Commitlog Sync Active [active-write-await-commitlog-sync]
Write Await Commitlog Sync Active
TP: Write Await Commitlog Segment Completed [completed-write-await-commitlog-segment]
Write Await Commitlog Segment Completed
TP: Write Await Commitlog Sync Completed [completed-write-await-commitlog-sync]
Write Await Commitlog Sync Completed

Compaction Executor

TP: Compaction Executor Pending [pending-compaction-executor]
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-compaction-executor]
Active compactions that are known.
TP: Compaction Executor Completed [completed-compaction-executor]
Completed compactions.

Counter Acquire Lock

TP: Counter Acquire Lock Active [active-counter-acquire-lock]
Counter Acquire Lock Active
TP: Counter Acquire Lock Completed [completed-counter-acquire-lock]
Counter Acquire Lock Completed

Execute Statements

TP: Execute Statement Active [active-execute-statement]
Execute Statement Active
TP: Execute Statement Completed [completed-execute-statement]
Execute Statement Completed

Flushes (memtables)

TP: Flushes Pending [pending-flushes]
Number of memtables queued for the flush process. A flush sorts and writes the memtables to disk.
TP: Post Flushes Pending [pending-memtable-post-flush]
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 [active-flushes]
Up to memtable_flush_writers concurrent tasks to flush and write the memtables to disk.
TP: Post Flushes Active [active-memtable-post-flush]
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 [completed-flushes]
Number of memtables flushed to disk since the nodes start.
TP: Post Flushes Completed [completed-memtable-post-flush]
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 [active-frame-decode]
Frame Decode Active
TP: Frame Decode Completed [completed-frame-decode]
Frame Decode Completed

Gossip

TP: Gossip Tasks Pending [pending-gossip-stage]
Number of gossip messages and acknowledgments queued and waiting to be sent or received.
TP: Gossip Tasks Active [active-gossip-stage]
Number of gossip messages and acknowledgments actively being sent or received.
TP: Gossip Tasks Completed [completed-gossip-stage]
Number of gossip messages and acknowledgments recently sent or received.

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

TP: Hint Dispatch Active [active-hint-dispatch]
Hint Dispatch Active
TP: Hint Dispatch Pending [pending-hint-dispatch]
Hint Dispatch Pending
TP: Hint Dispatch Completed [completed-hint-dispatch]
Hint Dispatch Completed
TP: Hint Dispatch Total Blocked [total-blocked-hint-dispatch]
Total Hint Dispatch Blocked
TP: Hint Dispatcher Active [active-hint-dispatcher]
Up to max_hints_delivery_threads tasks, each dispatching all hinted handoffs to a host.
TP: Hint Dispatcher Pending [pending-hint-dispatcher]
Pending tasks to send the stored hinted handoffs to a host.
TP: Hint Dispatcher Completed [completed-hint-dispatcher]
Number of tasks to transfer hints to a host that have completed.

Hint Response

TP: Hint Response Active [active-hint-response]
Hint Response Active
TP: Hint Response Completed [completed-hint-response]
Hint Response Completed

Locks

TP: Counter Acquire Lock Active [active-counter-acquire-lock]
Counter Acquire Lock Active
TP: Counter Acquire Lock Completed [completed-counter-acquire-lock]
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 [pending-lwt-propose]
Lwt Propose Pending
TP: Lwt Propose Active [active-lwt-propose]
Lwt Propose Active
TP: Lwt Propose Completed [completed-lwt-propose]
Lwt Propose Completed
TP: Lwt Prepare Active [active-lwt-prepare]
Lwt Prepare Active
TP: Lwt Prepare Pending [pending-lwt-prepare]
Lwt Prepare Pending
TP: Lwt Prepare Completed [completed-lwt-prepare]
Lwt Prepare Completed
TP: Lwt Commit Pending [pending-lwt-commit]
Lwt Commit Pending
TP: Lwt Commit Active [active-lwt-commit]
Lwt Commit Active
TP: Lwt Commit Completed [completed-lwt-commit]
Lwt Commit Completed
TP: Lwt Commit Total Blocked [total-blocked-lwt-commit]
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 [memtable-reclaim-active]
Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.
TP: Memtable Reclaims Pending [memtable-reclaim-pending]
Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.
TP: Memtable Reclaims Completed [completed-memtable-reclaim]
Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.

Migrations

TP: Migrations Pending [pending-migration-stage]
Number of pending tasks from system methods that modified the schema.
TP: Migrations Active [active-migration-stage]
Number of active tasks from system methods that modified the schema.
TP: Migrations Completed [completed-migration-stage]
Number of completed tasks from system methods that modified the schema.

NodeSync Validation

TP: NodeSync Validation Active [active-nodesync-validation]
NodeSync Validation Active
TP: NodeSync Validation Completed [completed-nodesync-validation]
NodeSync Validation Completed

Reads

TP: Read Disk Async Active [active-read-disk-async]
Read Disk Async Active
TP: Read Disk Async Completed [completed-read-disk-async]
Read Disk Async Completed
TP: Read Secondary Index Active [active-read-secondary-index]
Read Secondary Index Active
TP: Read Secondary Index Completed [completed-read-secondary-index]
Read Secondary Index Completed

Read Range NodeSync

TP: Read Range NodeSync Active [active-read-range-nodesync]
Read Range NodeSync Active
TP: Read Range NodeSync Pending [pending-read-range-nodesync]
Read Range NodeSync Pending
TP: Read Range NodeSync Completed [completed-read-range-nodesync]
Read Range NodeSync Completed
TP: Read Range NodeSync Total Blocked [total-blocked-read-range-nodesync]
Total Read Range NodeSync Blocked

Writes

TP: Write Switch For Memtable Active [active-write-switch-for-memtable]
Write Switch For Memtable Active
TP: Write Switch For Memtable Completed [completed-write-switch-for-memtable]
Write Switch For Memtable Completed

Timed Timeout and Timed Unknown

TP: Timed Timeout Active [active-timed-timeout]
Timed Timeout Active
TP: Timed Timeout Completed [completed-timed-timeout]
Timed Timeout Completed
TP: Timed Unknown Active [active-timed-unknown]
Timed Unknown Active
TP: Timed Unknown Completed [completed-timed-unknown]
Timed Unknown Completed

Truncate

TP: Truncate Active [active-truncate]
Truncate Active
TP: Truncate Completed [completed-truncate]
Truncate Completed

Unknown

Unknown thread pool metrics monitor threads for undetermined processes.

TP: Unknown Active [active-unknown]
Unknown Active
TP: Unknown Completed [completed-unknown]
Unknown Completed

View Build Executor

TP: View Build Executor Active [active-view-build-executor]
View Build Executor Active
TP: View Build Executor Pending [pending-view-build-executor]
View Build Executor Pending
TP: View Build Executor Completed [completed-view-build-executor]
View Build Executor Completed

Write Await Commit Log Segment and Sync

TP: Write Await Commitlog Segment Active [active-write-await-commitlog-segment]
Write Await Commitlog Segment Active
TP: Write Await Commitlog Segment Completed [completed-write-await-commitlog-segment]
Write Await Commitlog Segment Completed
TP: Write Await Commitlog Sync Active [active-write-await-commitlog-sync]
Write Await Commitlog Sync Active
TP: Write Await Commitlog Sync Completed [completed-write-await-commitlog-sync]
Write Await Commitlog Sync Completed

Write Defragment

TP: Write Defragment Active [active-write-defragment]
Write Defragment Active
TP: Write Defragment Pending [pending-write-defragment]
Write Defragment Pending
TP: Write Defragment Completed [completed-write-defragment]
Write Defragment Completed
TP: Write Defragment Total Blocked [total-blocked-write-defragment]
Total Write Defragment Blocked

Write Internal

TP: Write Internal Active [active-write-internal]
Write Internal Active
TP: Write Internal Completed [completed-write-internal]
Write Internal Completed

Write Local

TP: Write Local Active [active-write-local]
Write Local Active
TP: Write Local Pending [pending-write-local]
Write Local Pending
TP: Write Local Completed [completed-write-local]
Write Local Completed
TP: Write Local Total Blocked [total-blocked-write-local]
Total Write Local Blocked

Write Remote

TP: Write Remote Active [active-write-remote]
Write Remote Active
TP: Write Remote Pending [pending-write-remote]
Write Remote Pending
TP: Write Remote Completed [completed-write-remote]
Write Remote Completed
TP: Write Remote Total Blocked [total-blocked-write-remote]
Total Write Remote Blocked
TP: Write Switch For Memtable Active [active-write-switch-for-memtable]
Write Switch For Memtable Active

Write Switch (Memtables, Response)

TP: Write Switch For Memtable Active [active-write-switch-for-memtable]
Write Switch For Memtable Active
TP: Write Switch For Memtable Completed [completed-write-switch-for-memtable]
Write Switch For Memtable Completed
TP: Write Switch For Response Active [active-write-switch-for-response]
Write Switch For Response Active
TP: Write Switch For Response Completed [completed-write-switch-for-response]
Write Switch For Response Completed