Eon Mode Parameters

The following parameters configure how the database operates when running in Eon Mode. Query system table CONFIGURATION_PARAMETERS to determine what levels (node, session, user, database) are valid for a given parameter.

Parameter Description
CatalogSyncInterval

Specifies in minutes how often the transaction log sync service syncs metadata to S3. This value can be cluster or node specific.

Default: 5

DelayForDeletes

Specifies in hours how long to wait before deleting a file from communal storage. Vertica first deletes a file from the depot. After the specified time interval, the delete also occurs in communal storage.

Default: 0. Deletes the file from communal storage as soon as it is not in use by shard subscribers.

DepotOperationsForQuery

Specifies behavior when the depot does not contain queried file data, one of the following:

  • ALL (default): Fetch file data from communal storage, if necessary displace existing files by evicting them from the depot.
  • FETCHES: Fetch file data from communal storage only if space is available; otherwise, read the queried data directly from communal storage.
  • NONE: Do not fetch file data to the depot, read the queried data directly from communal storage.

You can also specify query-level behavior with the hint DEPOT_FETCH.

ECSMode

String parameter that sets the strategy Vertica uses when dividing the data in a shard among subscribing nodes during an ECS-enabled query. Value values are:

  • 'AUTO'—tells the optimizer to determine the strategy to use automatically.
  • 'COMPUTE_OPTIMIZED'—Force the use of the compute-optimized strategy.
  • 'IO_OPTIMIZED'—force the use of the I/O-optimized strategy.

See Manually Choosing an ECS Strategy for more information.

Default: 'AUTO'

EnableDepotWarmingFromPeers

Boolean parameter, specifies whether Vertica warms a node depot while the node is coming up and not ready to process queries:

  • 1: Warm the depot while a node comes up.
  • 0: Warm the depot only when the node is up.

Warming the depot involves inspecting the depots of other nodes and pre-fetching most recently used files. This task prepares the node to participate in queries without performance hits.

Default: 1

FileDeletionServiceInterval

Specifies in seconds the interval between each execution of the reaper cleaner service task.

Default: 60 seconds

ReaperCleanUpTimeoutAtShutdown

Specifies in seconds how long Vertica waits for the reaper to delete files from communal storage before shutting down. If set to a negative value, Vertica shuts down without waiting for the reaper.

The reaper is a service task that deletes disk files.

Default: 300

StorageMergeMaxTempCacheMB

The size of temp space allocated per query to the StorageMerge operator for caching the data of S3 storage containers.

The actual temp space that is allocated is the lesser of two settings:

For details, see Local Caching of Storage Containers.

UseCommunalStorageForBatchDepotWarming

Boolean parameter, specifies whether where a node retrieves data when warming its depot:

  • 1: Retrieve data from communal storage.
  • 0: Retrieve data from a peer.

The actual temp space that is allocated is the lesser of two settings:

Default: 1

This parameter is for internal use only. Do not change it unless directed to do so by Vertica support.

UseDepotForReads

Boolean parameter, specifies whether Vertica accesses the depot to answer queries, or accesses only communal storage:

  • 1Vertica first searches the depot for the queried data; if not there, Vertica fetches the data from communal storage for this and future queries.
  • 0Vertica bypasses the depot and always obtains queried data from communal storage.

Enable depot reads to improve query performance and support K-safety.

Default: 1

UseDepotForWrites

Boolean parameter, specifies whether Vertica writes loaded data to the depot and then uploads files to communal storage:

  • 1: Write loaded data to the depot, upload files to communal storage.
  • 0:  Bypass the depot and always write directly to communal storage.

Default: 1

UsePeerToPeerDataTransfer

Boolean parameter, specifies whether Vertica pushes loaded data to other shard subscribers:

  • 1: Send loaded data to all shard subscribers.
  • 0: Do not push data to other shard subscribers.

Setting to 1 helps improve performance when a node is down.

Default: 0

This parameter is for internal use only. Do not change it unless directed to do so by Vertica support.