============= Release 0.188

General Changes

Fix handling of negative start indexes in array :func:!slice function.
Fix inverted sign for time zones Etc/GMT-12, Etc/GMT-11, ..., Etc/GMT-1, Etc/GMT+1, ... Etc/GMT+12.
Improve performance of server logging and HTTP request logging.
Reduce GC spikes by compacting join memory over time instead of all at once when memory is low. This can increase reliability at the cost of additional CPU. This can be enabled via the pages-index.eager-compaction-enabled config property.
Improve performance of and reduce GC overhead for compaction of in-memory data structures, primarily used in joins.
Mitigate excessive GC and degraded query performance by forcing expiration of generated classes for functions and expressions one hour after generation.
Mitigate performance issue caused by JVM when generated code is used for multiple hours or days.

Fix transaction support. Previously, after the first statement in the transaction, the transaction would be abandoned and the session would silently revert to auto-commit mode.

Add environment support to the db resource groups manager. Previously, configurations for different clusters had to be stored in separate databases. With this change, different cluster configurations can be stored in the same table and Presto will use the new environment column to differentiate them.