Mihaly Szjatinya 22723d0f27 IMPALA-7086: Cache timezone in *_utc_timestamp() ...

Added Prepare - Close routine around from/to_utc standard functions.
This gives a consistent time improvement for constant timezones.

Given sample table with 600M timestamp rows, on all-default
environment the query below gives a stable 2-3 seconds improvement.
SELECT count(*) FROM a_table
where from_utc_timestamp(ts, "a_timezone") > "a_date";

Averaged results for Release, SET MT_OP=1, SET DISABLE_CODEGEN=TRUE:
from_utc: 16,53s -> 12,53s
to_utc: 14,02 - > 11,53

Change-Id: Icdf5ff82c5d0554333aef1bc3bba034a4cf48230
Reviewed-on: http://gerrit.cloudera.org:8080/21735
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>

2024-09-06 18:08:26 +00:00

96 KiB

Raw Blame History

View Raw