[mythtv-users] 'Wakeup' Delay on Idle Frontend

[Michael T. Dean]

On 12/23/2009 11:47 AM, Jim Stichnoth wrote:
> On Wed, Dec 23, 2009 at 5:28 AM, Jim Stichnoth <stichnot at gmail.com> wrote:
>   
>> I wonder if this is due to changeset 17834
>> (http://svn.mythtv.org/trac/changeset/17834) which added the
>> MDBManager::PurgeIdleConnections() function.  This function is run
>> when a new DB connection is initiated, and "cleans up" items in the DB
>> connection pool that have been idle for at least 1 hour.  Presumably
>> some interaction between Myth, QT, and MySQL is causing this.
>>
>> I can try a few things:
>>
>> * Disable the PurgeIdleConnections() function.
>>     
> This seems to make the problem go away.  Specifically, I just put a
> "return;" statement at the beginning of void
> MDBManager::PurgeIdleConnections() and I did not see the problem
> again.  Of course, that allows the problem addressed in changeset
> 17834 to come back.
>   

Now (with PurgeIdleConnections() disabled), get MySQL to timeout 
connections:

http://www.gossamer-threads.com/lists/mythtv/users/372194#372194
http://www.gossamer-threads.com/lists/mythtv/users/383430#383430
http://www.gossamer-threads.com/lists/mythtv/users/389517#389517

(especially interesting to this thread is the last para of that last 
post--"I've heard reports that some versions of MySQL/MySQL 
libs/Qt-MySQL drivers/something cause huge delays when Myth needs to 
reconnect.")

I'll bet you'll see the same behavior.

Mike