BACKGROUND_DEPOT_WARMING
Eon Mode only
Deprecated
Vertica version 10.0.0 removes support for foreground depot warming. When enabled, depot warming always happens in the background. Because foreground depot warming no longer exists, this function serves no purpose and has been deprecated. Calling it has no effect.Forces a node that is warming its depot to start processing queries while continuing to warm its depot in the background. Depot warming only occurs when a node is joining the database and is activating its subscriptions. This function only has an effect if:
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The database is running in Eon Mode.
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The node is currently warming its depot.
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The node is warming its depot from communal storage. This is the case when the UseCommunalStorageForBatchDepotWarming configuration parameter is set to the default value of 1. See Eon Mode parameters for more information about this parameter.
After calling this function, the node warms its depot in the background while taking part in queries.
This function has no effect on a node that is not warming its depot.
This is a meta-function. You must call meta-functions in a top-level SELECT statement.
Behavior type
VolatileSyntax
BACKGROUND_DEPOT_WARMING('node-name' [, 'subscription-name'])
Arguments
node-name
- The name of the node that you want to warm its depot in the background.
subscription-name
- The name of a shard that the node subscribes to that you want the node to warm in the background. You can find the names of the shards a node subscribes to in the SHARD_NAME column of the NODE_SUBSCRIPTIONS system table.
Note
When you supply the name of a specific shard subscription to warm in the background, the node may not immediately begin processing queries. It continues to warm any other shard subscriptions in the foreground if they are not yet warm. The node does not begin taking part in queries until it finishes warming the other subscriptions.
Return value
A message indicating that the node's warming will continue in the background.
Privileges
The user must be a superuser .
Examples
The following example demonstrates having node 6 of the verticadb database warm its depot in the background:
=> SELECT BACKGROUND_DEPOT_WARMING('v_verticadb_node0006');
BACKGROUND_DEPOT_WARMING
----------------------------------------------------------------------------
Depot warming running in background. Check monitoring tables for progress.
(1 row)