Aurora MySQL database engine updates: 2016-08-30 (version 1.7.0) (Deprecated) - Amazon Aurora

Aurora MySQL database engine updates: 2016-08-30 (version 1.7.0) (Deprecated)

Version: 1.7.0

New features

  • NUMA aware scheduler – The task scheduler for the Aurora MySQL engine is now Non-Uniform Memory Access (NUMA) aware. This minimizes cross-CPU socket contention resulting in improved performance throughput for the db.r3.8xlarge DB instance class.

  • Parallel read-ahead operates asynchronously in the background – Parallel read-ahead has been revised to improve performance by using a dedicated thread to reduce thread contention.

  • Improved index build (lab mode) – The implementation for building secondary indexes now operates by building the index in a bottom-up fashion, which eliminates unnecessary page splits. This can reduce the time needed to create an index or rebuild a table. This feature is disabled by default and can be activated by enabling Aurora lab mode. For information, see Amazon Aurora MySQL lab mode in the Amazon Aurora User Guide.

Improvements

  • Fixed an issue where establishing a connection was taking a long time if there was a surge in the number of connections requested for an instance.

  • Fixed an issue where a crash occurred if ALTER TABLE was run on a partitioned table that did not use InnoDB.

  • Fixed an issue where heavy write workload can cause a failover.

  • Fixed an erroneous assertion that caused a failure if RENAME TABLE was run on a partitioned table.

  • Improved stability when rolling back a transaction during insert-heavy workload.

  • Fixed an issue where full-text search indexes were not viable on an Aurora Replica.

Integration of MySQL bug fixes

  • Improve scalability by partitioning LOCK_grant lock. (Port WL #8355)

  • Opening cursor on SELECT in stored procedure causes segfault. (Port Bug #16499751)

  • MySQL gives the wrong result with some special usage. (Bug #11751794)

  • Crash in GET_SEL_ARG_FOR_KEYPART – caused by patch for bug #11751794. (Bug #16208709)

  • Wrong results for a simple query with GROUP BY. (Bug #17909656)

  • Extra rows on semijoin query with range predicates. (Bug #16221623)

  • Adding an ORDER BY clause following an IN subquery could cause duplicate rows to be returned. (Bug #16308085)

  • Crash with explain for a query with loose scan for GROUP BY, MyISAM. (Bug #16222245)

  • Loose index scan with quoted int predicate returns random data. (Bug #16394084)

  • If the optimizer was using a loose index scan, the server could exit while attempting to create a temporary table. (Bug #16436567)

  • COUNT(DISTINCT) should not count NULL values, but they were counted when the optimizer used loose index scan. (Bug #17222452)

  • If a query had both MIN()/MAX() and aggregate_function(DISTINCT) (for example, SUM(DISTINCT)) and was executed using loose index scan, the result values of MIN()/MAX() were set improperly. (Bug #17217128)