MV_ACTIVITIES_EXTENDED

This view provides a detailed profile of all tasks which ran recently on any node in the cluster.

It holds a row per activity. Each row describes the instances of its activity which ran during a recent interval of time. It reports the sum of the profiling statistics of each task in the set, as collected over the recent interval. Activities can include tasks such as garbage collection and backups, in addition to queries.

mv_activities determines recent resource use by computing the change in mv_activities_extended_cumulative over an interval of time. This interval is controlled by the value of the activities_delta_sleep_s session variable.

mv_activities_extended may only be queried while connected to an aggregator node.

SingleStore recommends using this view to get fine-grained understanding of the system behavior described in mv_activities. The main distinctions between mv_activities and mv_activities_extended are:

  • For most queries, mv_activities_extended will report the resource usage of the query with at least a row per partition.

  • mv_activities aggregates these into a single row per query.

  • mv_activities reports simplified statistics, while mv_activities_extended reports extended statistics.

However, SingleStore recommends against the use of mv_activities_extended to compute the average latency or resource usage of a query. This is because its statistics include the latency and resource usage of currently running tasks, which will skew attempted average calculations. SingleStore recommends mv_finished_tasks for this purpose instead.

Column name

Description

node_id

An id equal to id in the row of mv_nodes describing the node on which the instances ran.

activity_type

The type of the activity.

activity_name

The name of the activity. This column is often human-readable, but does not include the full query text for query tasks. Join with mv_queries for the query text.

aggregator_activity_name

The aggregator activity name of the activity.

database_name

The name of the database associated with the activity, or NULL if none could be assigned.

partition_id

The unique ID of the database partition associated with the activity, or NULL if none could be assigned.

run_count

The number of instances which were running at the end of the interval.

success_count

The number of instances which completed successfully during the interval.

failure_count

The number of instances which completed unsuccessfully during the interval.

EXTENDED STATISTICS

This view contains all extended statistics columns.

Last modified: March 8, 2024

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