MySQL Bugs: #17635: Sleep time long process after time clock adjust in system

Bug #17635	Sleep time long process after time clock adjust in system
Submitted:	22 Feb 2006 2:56	Modified:	23 Jan 2007 20:51
Reporter:	Luis A S Junior Camargo	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server	Severity:	S3 (Non-critical)
Version:	5.0.18	OS:	Windows (Windows 2000 Server SP4)
Assigned to:	Magnus Blåudd	CPU Architecture:	Any

Description:
Sleep time value has bigger increasing after clock adjust in system.

How to repeat:
select sleep(3);
executed in 3 seconds

select sleep(5);
executed in 5 seconds

select sleep(10);
executed in 10 seconds

Change the time clock of system from 10:00 to 09:00 (for example)

select sleep(3);
after 30 minutes the query is not processed

select sleep(5);
after 30 minutes the query is not processed

select sleep(10);
after 30 minutes the query is not processed

Suggested fix:
I unknow, after restart the MySQL the problem is solved.

Finally the query is processed, i have changed the time clock at 5 days ago without restart the MySQL service, the wrong interval is equal with interval change in system,  this is a query result of my last post:

mysql> select sleep(0);
+----------+
| sleep(0) |
+----------+
|        0 |
+----------+
1 row in set (1 hour 7.75 sec)

mysql> select sleep(1);
+----------+
| sleep(1) |
+----------+
|        0 |
+----------+
1 row in set (1 hour 8.31 sec)

mysql> select sleep(10);
+-----------+
| sleep(10) |
+-----------+
|         0 |
+-----------+
1 row in set (1 hour 17.56 sec)

Thank you for the bug report. On Windows the sleep uses the Win32 API
Sleep() function:

#elif defined(__WIN__)
  Sleep(m_seconds/1000+1);      /* Sleep() has millisecond arg */
#elif defined(OS2)

Maybe another method can be used or just can't be fixed.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/14411

ChangeSet@1.2328, 2006-10-25 20:34:13-04:00, iggy@amd64. +1 -0
  Bug#17635 Sleep time long process after time clock adjust in system.
  - Windows version of my_getsystime() only checked the local system time
  the first time it was called.  Changes to system time would either delay
  or increase the sleep period by the amount of time changed.

Noted in 5.0.36, 5.1.15 changelogs.

On Windows, the SLEEP() function could sleep too long, especially
after a change to the system clock.