Bug #43421 LoadBalancingConnectionProxy.doPing() needs blacklist awareness

Description:
LoadBalancingConnectionProxy currently implements doPing() to ping all underlying connections, but it throws any Exceptions it encounters during this process.  If the global blacklist is enabled, it should instead catch these Exceptions, adding the host to the global blacklist, and only throwing an Exception if all hosts are down.

How to repeat:
Look at LoadBalancingConnectionProxy.doPing() code.

Suggested fix:
If global blacklist is enabled, catch Exceptions and add host to global blacklist.  If all hosts are down, throw Exception.

patch for feature and test case.

Attachment: diff.txt (text/plain), 7.40 KiB.

Updated patch with better asserts.

Attachment: diff.txt (text/plain), 7.21 KiB.

Revised locking patch.

Attachment: diff.txt (text/plain), 7.36 KiB.

Fixed patch

Attachment: diff.txt (text/plain), 7.43 KiB.

Pushed to 5.1 tree:

http://lists.mysql.com/commits/68563

will be released in 5.1.8

An entry was added to the 5.1.8 changelog:

LoadBalancingConnectionProxy.doPing() did not have blacklist awareness.

LoadBalancingConnectionProxy implemented doPing() to ping all underlying connections, but it threw any exceptions it encountered during this process.

With the global blacklist enabled, it catches these exceptions, adds the host to the global blacklist, and only throws an exception if all hosts are down.