RUNTIME_FILTER_MIN_SIZE Query Option (Impala 2.6 or higher only)

The RUNTIME_FILTER_MIN_SIZE query option adjusts the settings for the runtime filtering feature. This option defines the minimum size for a filter, no matter what the estimates produced by the planner are. This value also overrides any lower number specified for the RUNTIME_BLOOM_FILTER_SIZE query option. Filter sizes are rounded up to the nearest power of two.

Type: integer

Default: 0 (meaning use the value from the corresponding impalad startup option)

Added in: Impala 2.6.0

Usage notes:

Because the runtime filtering feature applies mainly to resource-intensive and long-running queries, only adjust this query option when tuning long-running queries involving some combination of large partitioned tables and joins involving large tables.

Kudu considerations:

This query option affects only Bloom filters, not the min/max filters that are applied to Kudu tables. Therefore, it does not affect the performance of queries against Kudu tables.

Related information:

Runtime Filtering for Impala Queries (Impala 2.5 or higher only), RUNTIME_FILTER_MODE Query Option (Impala 2.5 or higher only), RUNTIME_FILTER_MAX_SIZE Query Option (Impala 2.6 or higher only), RUNTIME_BLOOM_FILTER_SIZE Query Option (Impala 2.5 or higher only)