Re: [Maria-developers] Rev 3804: MDEV-4712 : Fix "shutdown" test

-----Original Message----- From: Sergei Golubchik [mailto:serg@mariadb.org] Sent: Donnerstag, 8. August 2013 18:29 To: maria-developers@lists.launchpad.net Cc: Vladislav Vaintroub Subject: Re: Rev 3804: MDEV-4712 : Fix "shutdown" test

Hi, Vladislav!

On Jul 31, Vladislav Vaintroub wrote:

...

------------------------------------------------------------ revno: 3804 revision-id: wlad@montyprogram.com-20130731130414-ukqxbb0kxpexjnzp parent: svoj@mariadb.org-20130731110211-09p66bwf4jrmi03i committer: Vladislav Vaintroub branch nick: 10.0-serg timestamp: Wed 2013-07-31 15:04:14 +0200 message: MDEV-4712 : Fix "shutdown" test.

There is a race condition during shutdown, that happens when "show status" runs during shutdown. Functions show_slave_running(), show_slave_received_heartbeats(), show_heartbeat_period() would dereference NULL pointer master_info_index, after this variable is set to NULL in slave_end() during shutdown. Fix introduces check for master_info_index == NULL in the affected functions.

Was it related to the new shutdown command? Or it could be also observed without it by, say, running show status in a loop, while stopping the server with mysqladmin?

Hi Serg, It is unrelated to shutdown command, and should be reproducible e.g with mysqladmin (though, I did not try and just used the "shutdown" test case)