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Task Timeout
An individual task invocation will run for
user_task_timeout_ms
before being cancelled
by Snowflake.
Concurrency
The number of concurrent processes executed by a warehouse can be set by
max_
concurrency_level
.
Execution Context
The current session execution context can be derived by this query:
SELECT current_account(),
current_user(),
current_role(),
current_warehouse(),
current_database(),
current_schema();
Clearing Warehouse Cache
To ensure raw performance figures are not skewed by the cache when testing or
investigating, ignore cached results causing every SQL statement to be executed.
ALTER SESSION SET use_cached_result = FALSE;
The warehouse declaration does not clear out the warehouse cache, so you must
suspend and restart the warehouse, which also aborts all the active SQL statements.
USE WAREHOUSE IDENTIFIER ( $tpc_warehouse_xs );
ALTER WAREHOUSE IDENTIFIER ( $tpc_warehouse_xs ) SUSPEND;
ALTER WAREHOUSE IDENTIFIER ( $tpc_warehouse_xs ) RESUME;
Micro-partition reclustering or consolidation causes cached result sets to be
invalidated preventing reuse.
ChapTer 10
OpTimizing perfOrmanCe