Bug #81487 innodb buf_resize_thread - release mutexes when no change (contribution)

• Submitted: 18 May 2016 12:45
• Modified: 19 May 2016 4:54
• Reporter: OCA Admin (OCA)
• Status: Not a Bug
• Category: MySQL Server: InnoDB storage engine
• Severity: S3 (Non-critical)
• Version: 5.7
• OS: Any
• Assigned to: Shaohua Wang
• CPU Architecture: Any

[18 May 2016 12:45] OCA Admin

Description:
This bug tracks a contribution by Daniel Black (Github user: grooverdan) as described in http://github.com/mysql/mysql-server/pull/74

How to repeat:
See description

Suggested fix:
See contribution code attached

[18 May 2016 12:45] OCA Admin

Contribution submitted via Github - innodb buf_resize_thread - release mutexes when no change 
(*) Contribution by Daniel Black (Github grooverdan, mysql-server/pull/74#issuecomment-219876297): I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

Contribution: git_patch_70308332.txt (text/plain), 1.03 KiB.

[18 May 2016 12:55] MySQL Verification Team

Hello Daniel,

Thank you for the report and contribution.

Thanks,
Umesh

[19 May 2016 4:14] Daniel Black

I made a mistake. This is invalid.

buf_pool_mutex_exit_all is called at the beginning of the 'if' statement which is sufficient. Sorry for the noise.

[19 May 2016 4:54] Shaohua Wang

We do release all mutexes in buf_resize_thread().

See https://github.com/mysql/mysql-server/blob/5.7/storage/innobase/buf/buf0buf.cc

buf_pool_mutex_enter_all();
		if (srv_buf_pool_old_size == srv_buf_pool_size) {
			buf_pool_mutex_exit_all();  -- released!!!
			std::ostringstream sout;
			sout << "Size did not change (old size = new size = "
				<< srv_buf_pool_size << ". Nothing to do.";
			buf_resize_status(sout.str().c_str());

			/* nothing to do */
			continue;
		}
		buf_pool_mutex_exit_all();