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
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) 

Metrics to monitor network back pressure:

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 Remove Blocked
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.

CAS 

TP: CAS Active
CAS Active
TP: CAS Completed
CAS Completed

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

Eventloop 

Metrics for park, spin, and yield eventloop.

TP: Eventloop Park Active
Eventloop Park Active
TP: Eventloop Park Completed
Eventloop Park Completed
TP: Eventloop Spin Active
Eventloop Spin Active
TP: Eventloop Spin Completed
Eventloop Spin Completed
TP: Eventloop Yield Active
Eventloop Yield Active
TP: Eventloop Yield Completed
Eventloop Yield 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 Pending
Frame Decode Pending
TP: Frame Decode Completed
Frame Decode Completed
TP: Frame Decode Total Blocked
Total Frame Decode Blocked

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