This commit is based on the work of Michal Schorm, rebased on the
earliest MariaDB version.
Th command line used to generate this diff was:
find ./ -type f \
-exec sed -i -e 's/Foundation, Inc., 59 Temple Place, Suite 330, Boston, /Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, /g' {} \; \
-exec sed -i -e 's/Foundation, Inc. 59 Temple Place.* Suite 330, Boston, /Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, /g' {} \; \
-exec sed -i -e 's/MA.*.....-1307.*USA/MA 02110-1335 USA/g' {} \; \
-exec sed -i -e 's/Foundation, Inc., 59 Temple/Foundation, Inc., 51 Franklin/g' {} \; \
-exec sed -i -e 's/Place, Suite 330, Boston, MA.*02111-1307.*USA/Street, Fifth Floor, Boston, MA 02110-1335 USA/g' {} \; \
-exec sed -i -e 's/MA.*.....-1307/MA 02110-1335/g' {} \;
The problem was that the introduction of max-thread-mem-used can cause
an allocation error very early, even before mysql_parse() is called.
As mysql_parse() calls thd->reset_for_next_command(), which called
clear_error(), the error number was lost.
Fixed by adding an option to have unique messages for each KILL
signal and change max-thread-mem-used to use this new feature.
This removes a lot of problems with the original approach, where
one could get errors signaled silenty almost any time.
ixed by moving clear_error() from reset_for_next_command() to
do_command(), before any memory allocation for the thread.
Related changes:
- reset_for_next_command() now have an optional parameter if we should
call clear_error() or not. By default it's called, but not anymore from
dispatch_command() which was the original problem.
- Added optional paramater to clear_error() to force calling of
reset_diagnostics_area(). Before clear_error() only called
reset_diagnostics_area() if there was no error, so we normally
called reset_diagnostics_area() twice.
- This change removed several duplicated calls to clear_error()
when starting a query.
- Reset max_mem_used on COM_QUIT, to protect against kill during
quit.
- Use fatal_error() instead of setting is_fatal_error (cleanup)
- Set fatal_error if max_thead_mem_used is signaled.
(Same logic we use for other places where we are out of resources)
Use post_kill_notification in for one_thread_per_connection scheduler,
the same as already used in threadpool, to reliably wake a thread stuck in
read() or in different poll() variations.
The problem was increment of aborted_threads variable due to thd->killed which was set when threadpool connection was terminated . The fix is not to set thd->killed anymore, there is no real reason for doing it..
Added a test that checks that status variable aborted_clients does not grow for ordinary disconnects, and that successful KILL increments this variable.
