Impala currently uses two different libraries for timestamp
manipulations: boost and glibc.
Issues with boost:
- Time-zone database is currently hard coded in timezone_db.cc.
Impala admins cannot update it without upgrading Impala.
- Time-zone database is flat, therefore can’t track year-to-year
changes.
- Time-zone database is not updated on a regular basis.
Issues with glibc:
- Uses /usr/share/zoneinfo/ database which could be out of sync on
some of the nodes in the Impala cluster.
- Uses the host system’s local time-zone. Different nodes in the
Impala cluster might use a different local time-zone.
- Conversion functions take a global lock, which causes severe
performance degradation.
In addition to the issues above, the fact that /usr/share/zoneinfo/
and the hard-coded boost time-zone database are both in use is a
source of inconsistency in itself.
This patch makes the following changes:
- Instead of boost and glibc, impalad uses Google's CCTZ to implement
time-zone conversions.
- Introduces a new startup flag (--hdfs_zone_info_zip) to impalad to
specify an HDFS/S3/ADLS path to a zip archive that contains the
shared compiled IANA time-zone database. If the startup flag is set,
impalad will use the specified time-zone database. Otherwise,
impalad will use the default /usr/share/zoneinfo time-zone database.
- Introduces a new startup flag (--hdfs_zone_alias_conf) to impalad to
specify an HDFS/S3/ADLS path to a shared config file that contains
definitions for non-standard time-zone aliases.
- impalad reads the entire time-zone database into an in-memory
map on startup for fast lookups.
- The name of the coordinator node’s local time-zone is saved to the
query context when preparing query execution. This time-zone is used
whenever the current time-zone is referred afterwards in an
execution node.
- Adds a new ZipUtil class to extract files from a zip archive. The
implementation is not vulnerable to Zip Slip.
Cherry-picks: not for 2.x.
Change-Id: I93c1fbffe81f067919706e30db0a34d0e58e7e77
Reviewed-on: http://gerrit.cloudera.org:8080/9986
Reviewed-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Reviewed-by: Attila Jeges <attilaj@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
