Bug #57627 Use atomic memory access instead of mutexes for updating counters

• Submitted: 21 Oct 2010 12:45
• Modified: 12 Jan 2011 22:08
• Reporter: Jimmy Yang
• Status: Closed
• Category: MySQL Server: InnoDB storage engine
• Severity: S3 (Non-critical)
• Version: 5.6
• OS: Any
• Assigned to: Jimmy Yang
• CPU Architecture: Any

[21 Oct 2010 12:45] Jimmy Yang

Description:
This is to update certain counters with atomic operation instead of doing so with mutex protection:

Added generic counter operation to increment/decrement following counters atomically if HAVE_ATOMIC_BUILTINS is defined:
 a) ios
 b) dict_table_t::n_foreign_key_checks_running
 c) trx_sys->rseg_history_len

We will fall back to mutex protection for "n_foreign_key_checks_running" and "rseg_history_len" if  HAVE_ATOMIC_BUILTINS not defined.

How to repeat:
Go through corresponding code.

[13 Nov 2010 16:10] Bugs System

Pushed into mysql-trunk 5.6.99-m5 (revid:[e-mail]-20101113155825-czmva9kg4n31anmu) (version source revid:[e-mail]-20101113152450-2zzcm50e7i4j35v7) (merge vers: 5.6.1-m4) (pib:21)

[13 Nov 2010 16:42] Bugs System

Pushed into mysql-next-mr (revid:[e-mail]-20101113160336-atmtmfb3mzm4pz4i) (version source revid:[e-mail]-20101113152540-gxro4g0v29l27f5x) (pib:21)