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Percona Server 5.7.21-20 (2018-02-19)

Percona is glad to announce the release of Percona Server 5.7.21-20 on February 19, 2018. Downloads are available here and from the Percona Software Repositories.

This release is based on MySQL 5.7.21 and includes all the bug fixes in it. Percona Server 5.7.21-20 is now the current GA (Generally Available) release in the 5.7 series. All software developed by Percona is open-source and free.

New Features

  • A new string variable version_suffix allows changing suffix for the Percona Server for MySQL version string returned by the read-only version variable. Also version_comment is converted from a global read-only to a global read-write variable.

  • A new keyring_vault_timeout variable allows setting the number of seconds for the Vault server connection timeout. Bug fixed #298.

Bugs Fixed

  • The mysqld startup script was unable to detect jemalloc library location for preloading, and that prevented starting the Percona Server for MySQL on systemd-based machines. Bugs fixed #3784 and #3791.

  • There was a problem with fulltext search, which could find a word with punctuation marks in natural language mode only, but not in boolean mode. Bugs fixed #258, #2501 (upstream #86164).

  • Build errors were present on FreeBSD (caused by fixing the bug #255 in Percona Server for MySQL 5.6.38-83.0 and on MacOS (caused by fixing the bug #264 in Percona Server for MySQL 5.7.20-19. Bugs fixed #2284 and #2286.

  • A bunch of fixes were introduced to remove GCC 7 compilation warnings for the Percona Server for MySQL build. Bugs fixed #3780 (upstream #89420, #89421, and #89422).

  • CMake error took place at compilation with bundled zlib. Bug fixed #302.

  • A GCC 7 warning fix introduced a regression in Percona Server for MySQL that led to a wrong SQL query built to access the remote server when the Federated storage engine was used. Bug fixed #1134.

  • It was possible to enable encrypt_binlog with no binary or relay logging enabled. Bug fixed #287.

  • Long buffer wait times were occurring on busy servers in case of the IMPORT TABLESPACE command. Bug fixed #276.

  • Server queries that contained JSON special characters and were logged by Audit Log Plugin in JSON format caused invalid output due to lack of escaping. Bug fixed #1115.

  • Percona Server now uses Travis CI for additional tests. Bug fixed #3777.

Other bugs fixed: #257, #264, #1090 (upstream #78048), #1109, #1127, #2204, #2414, #2415, #3767, #3794, and #3804 (upstream #89598).

This release also contains fixes for the following CVE issues: CVE-2018-2565, CVE-2018-2573, CVE-2018-2576, CVE-2018-2583, CVE-2018-2586, CVE-2018-2590, CVE-2018-2612, CVE-2018-2600, CVE-2018-2622, CVE-2018-2640, CVE-2018-2645, CVE-2018-2646, CVE-2018-2647, CVE-2018-2665, CVE-2018-2667, CVE-2018-2668, CVE-2018-2696, CVE-2018-2703, CVE-2017-3737.

MyRocks Changes

  • A new behavior makes Percona Server for MySQL fail to restart on detected data corruption; rocksdb_allow_to_start_after_corruption variable can be passed to mysqld as a command line parameter to switch off this restart failure.

  • A new cmake option ALLOW_NO_SSE42 was introduced to allow MyRocks build on hosts not supporting SSE 4.2 instructions set, which makes MyRocks usable without FastCRC32-capable hardware. Bug fixed MYR-207.

  • rocksdb_bytes_per_sync and rocksdb_wal_bytes_per_sync variables were turned into dynamic ones.

  • rocksdb_flush_memtable_on_analyze variable has been removed.

  • rocksdb_concurrent_prepare is now deprecated, as it has been renamed in upstream to rocksdb_two_write_queues.

  • rocksdb_row_lock_deadlocks and rocksdb_row_lock_wait_timeouts global status counters were added to track the number of deadlocks and the number of row lock wait timeouts.

  • Creating a table with string indexed column to non-binary collation now generates a warning about using inefficient collation instead of an error. Bug fixed MYR-223.

TokuDB Changes

  • A memory leak was fixed in the PerconaFT library, caused by not destroying PFS key objects on shutdown. Bug fixed TDB-98.

  • A clang-format configuration was added to PerconaFT and TokuDB. Bug fixed TDB-104.

  • A data race was fixed in minicron utility of the PerconaFT. Bug fixed TDB-107.

  • Row count and cardinality decrease to zero took place after long-running REPLACE load.

Other bugs fixed: TDB-48, TDB-78, TDB-93, and TDB-99.