Returns counters for the ThingsDB node in the selected scope. Counters start all at zero when ThingsDB
is started, or when the counters are reset by using reset_counters()'.
Counters give information about things, queries and changes. If you suspect failed queries, then the counters might provide you with more information.
| Counter | Description |
|---|---|
| average_change_duration | The average change duration in seconds. Change duration is measured from the time a change is created (before the final Id is assigned), until the actual change is committed to ThingsDB. |
| average_query_duration | The average query duration in seconds. Query duration is measured from the time a query (or procedure run) request is unpacked, until the response is created to send back to the client. |
| changes_committed | Changes committed since last the counters reset. |
| changes_failed | Failed changes. This is a critical counter which should be 0. |
| changes_killed | Killed changes took too long for receiving the READY status. These changes may be processed later. |
| changes_skipped | Changes which cannot be committed since a change with a higher id is already processed. |
| changes_unaligned | Number of times a change cannot be pushed to the end of the queue and needs re-ordering. |
| changes_with_gap | Changes which are committed but at least one change-Id was skipped. |
| garbage_collected | Number of things which are garbage collected. |
| largest_result_size | Largest query result size in bytes. Check node_info() to see the maximum allowed query result size. |
| longest_change_duration | Longest change duration, in seconds. Change duration is measured from the moment a change is created, until the change is finished. During AWAY mode, a node will still create changes, but waits before processing changes and thus may result in rather long duration values. |
| longest_query_duration | Longest query duration, in seconds. |
| queries_from_cache | Number of queries which are loaded from cache. |
| queries_success | Number of queries where this node acted as the master node and the query has successful finished. |
| queries_with_error | Number of queries where this node acted as the master node but the query has returned with an error. |
| quorum_lost | Number of times this node did not get a change Id accepted by the quorum of nodes. a change-Id will not be accepted if another node is attempting to assign the same change-Id. This is not an issue since the node will just try another change-Id. It only indicates the number of collisions occurred while trying to assign a change Id. |
| started_at | UNIX time-stamp in seconds when the counters started counting. See reset_counters(). |
| tasks_success | Number of successfully processed tasks. |
| tasks_with_error | Number of processed tasks where the task returned with an error. |
| wasted_cache | Number of cached queries which are cleaned from the cache without ever being used. |
This function does not generate a change.
counters()
None
Returns the current counter values.
This code will return node counter values:
// Returns the current counters for the node in this scope
counters();
Example return value in JSON format
{
"average_change_duration": 0.032120732,
"average_query_duration": 0.009859586882352942,
"changes_committed": 1,
"changes_failed": 0,
"changes_killed": 0,
"changes_skipped": 0,
"changes_unaligned": 0,
"changes_with_gap": 0,
"garbage_collected": 0,
"largest_result_size": 1247,
"longest_change_duration": 0.032120732,
"longest_query_duration": 0.066440648,
"queries_from_cache": 1,
"queries_success": 17,
"queries_with_error": 0,
"quorum_lost": 0,
"started_at": 1627903017,
"tasks_success": 0,
"tasks_with_error": 0,
"wasted_cache": 0,
"watcher_failed": 0
}