MV_ACTIVITIES_CUMULATIVE

This view provides a high-level summary profile of completed and currently running tasks on all nodes of the workspace.

It holds a row per high-level activity H. Each row describes tasks which have completed or are currently running, and which are either instances of the high level activity H, or else instances of an activity L whose aggregator activity name is the name of H. It reports the sum of the profiling statistics of each task in the set, as collected over its lifetime. Activities can include tasks such as garbage collection and backups, in addition to queries.

The effect of grouping the instances of multiple activities together is mainly to group all tasks associated with a query, across all partitions, into a single row.

For cross-database queries, activities in this table are tracked in relation to the context database of the local query. For activities on an aggregator, this is the context database of the session. For activities on leaves, this is the context database chosen by the optimizer for each part of the query. In general, leaf activities occur on the database that stores the table(s) being queried.

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

SingleStore recommends against extensive use of this table. It does not accurately describe past system behavior because it doesn’t include all completed instances. This is because historical task statistics may be discarded by SingleStore Helios at unspecified times.

Column name

Description

activity_type

The type of the activities.

activity_name

An ID shared by all instances of the high level activity. This ID is often human-readable, but does not include the query text for query tasks. See mv_queries for the raw query text.

database_name

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

last_finished_timestamp

The timestamp of the most recent completion of an instance of this activity.

run_count

The number of running instances of the activity.

success_count

The number of successfully completed instances of the activity.

failure_count

The number of unsuccessfully completed instances of the activity.

SIMPLIFIED STATISTICS

This view contains all simplified statistics columns.

BLOB_CACHE_MISS_B

A query sometimes cannot find its input data in blob cache, referred to as a cache miss. The blob cache will download the missing data from the unlimited storage. This new field tells us the number of bytes downloaded from the unlimited storage.

BLOB_CACHE_WAIT_TIME_MS

The time (milliseconds) that were spent on waiting for blob cache data. This is a sum of waiting time from all query execution threads, not to be compared with end-to-end running time.

Last modified: January 25, 2024

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