Data Collector utility
The Data Collector collects and retains history of important system activities and records essential performance and resource utilization counters. The Data Collector propagates information to system tables.
You can use the Data Collector in the following ways:
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Query the past state of system tables and extract aggregate information
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See what actions users have taken
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Locate performance bottlenecks
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Identify potential improvements to Vertica configuration
The Data Collector does not collect data for nodes that are down, so no historical data is available for affected nodes.
The Data Collector works with Workload Analyzer, a tool that intelligently monitors the performance of SQL queries and workloads and recommends tuning actions based on observations of the actual workload history.
Configuring and accessing Data Collector information
The Data Collector retains the data it gathers according to configurable retention policies. The Data Collector is on by default; you can disable it by setting the EnableDataCollector configuration parameter to 0. You can set the parameter at the database level using ALTER DATABASE or the node level using ALTER NODE. You cannot set it at the session or user level.
You can access metadata on collected data of all components using the DATA_COLLECTOR system table. This table includes information for each component about current collection policies and how much data is retained in memory and on disk.
Collected data is logged on disk in the DataCollector
directory under the Vertica /catalog
path. You can query logged data from component-specific Data Collector tables. You can also manage logged data with Vertica meta-functions; see Managing data collection logs.