New Features
Percona Server has extended the SELECT INTO ... OUTFILE and SELECT INTO DUMPFILE to add the support for UNIX sockets and named pipes.
Percona Server now provides additional information in the slow query log when log_slow_rate_limit variable is enabled.
A new variable slow_query_log_always_write_time has been introduced. It can be used to specify an additional execution time threshold for the slow query log, that, when exceeded, will cause a query to be logged unconditionally, that is, log_slow_rate_limit will not apply to it.
Utility user feature has been extended by adding a new utility_user_privileges that allows a comma separated value list of extra access privileges that can be granted to the utility user.
Bugs Fixed
Due to an incompatible upstream change that went in unnoticed, the log tracker thread would attempt to replay any file operations it encountered. In most cases this were a no-op, but there were race conditions for certain DDL operations that would have resulted in server crash. Bug fixed #1217002.
apt-get upgrade of Percona Server would fail in post-installation step if server failed to start. Bug fixed #1002500.
Fixed the libssl.so.6 dependency issues in binary tarballs releases. Bug fixed #1172916.
Error in install_layout.cmake could cause that some library files, during the build, end up in different directories on x86_64 environment. Bug fixed #1174300.
Percona Server could crash while accessing BLOB or TEXT columns in InnoDB tables if Support for Fake Changes was enabled. Bug fixed #1188168.
Memory leak was introduced by the fix for bug #1132194. Bug fixed #1204873.
The unnecessary overhead from persistent InnoDB adaptive hash index latching has been removed, potentially improving stability of the Multiple Adaptive Hash Search Partitions feature as well. Upstream bug fixed #70216, bug fixed #1218347.
Fixed the incorrect dependency with libmysqlclient18-dev from Percona Server 5.5.33-31.1. Bug fixed #1237097.
A memory leak in Utility user feature has been fixed. Bug fixed #1166638.
Expanded Program Option Modifiers did not deallocate memory correctly. Bug fixed #1167487.
A server could crash due to a race condition between a INNODB_CHANGED_PAGES query and a bitmap file delete by PURGE CHANGED_PAGE_BITMAP or directly on the file system. Bug fixed #1191580.
Percona Server could not be built with Thread Pool feature and -DWITH_PERFSCHEMA_ENGINE=OFF option. Bug fixed #1196383.
Building Percona Server with -DHAVE_PURIFY option would result in an error. Fixed by porting the close_socket function from MariaDB. Bug fixed #1203567.
Adaptive hash index memory size was incorrectly calculated in SHOW ENGINE INNODB STATUS and Innodb_mem_adaptive_hash status variable. Bug fixed #1218330.
Some Expanded Program Option Modifiers didn’t have an effect if they were specified in non-normalized way (innodb_io_capacity vs innodb-io-capacity). Bug fixed #1233294.
Enabling Enforcing Storage Engine feature could lead to error on Percona Server shutdown. Bug fixed #1233354.
Storage engine enforcement (enforce_storage_engine) is now ignored when the server is started in either bootstrap or skip-grant-tables mode. Bug fixed #1236938.
Fixed the build warnings caused by User Statistics code on non-Linux platforms. Bug fixed #711817.
Adaptive hash indexing partitioning code has been simplified, potentially improving performance. Bug fixed #1218321.
Other bugs fixed: bug fixed #1239630, bug fixed #1191589, bug fixed #1200162, bug fixed #1214449, and bug fixed #1190604.
