MV_FINISHED_TASKS

This view provides a detailed profile of completed tasks on all nodes of the cluster.

It holds a row per activity. Each row describes completed instances of its activity. It reports the sum of the profiling statistics of each instance, as collected over its lifetime.

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

SingleStore recommends against extensive use of this view. It does not accurately describe past system behavior because it doesn’t include all completed instances. It will also hide the performance impact of long-running tasks which have yet to complete.

However, we do recommend using this view to estimate the average latency or resource usage of a query. This is because all other statistics tables include currently running tasks in their profiles, skewing attempted average calculations.

Column name

Description

node_id

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

activity_type

The type of the activity.

activity_name

An ID shared by all instances of the activity. This ID is often human-readable, but does not include the 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.

last_finished_timestamp

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

success_count

The number of successfully completed instances of this activity.

failure_count

The number of unsuccessfully completed instances of this activity.

EXTENDED STATISTICS

This view contains all extended 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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