Merged from mysql-wsrep-bugs following:
GCF-1058 MTR test galera.MW-86 fails on repeated runs
Wait for the sync point sync.wsrep_apply_cb to be reached before
executing the test and clearing the debug flag sync.wsrep_apply_cb.
The race scenario:
Intended behavior:
node2: set sync.wsrep_apply_cb in order to start waiting in the background INSERT
node1: INSERT start
node2 (background): INSERT start
node1: INSERT end
node2: send signal to background INSERT: "stop waiting and continue executing"
node2: clear sync.wsrep_apply_cb as no longer needed
node2 (background): consume the signal
node2 (background): INSERT end
node2: DROP TABLE
node2: check no pending signals are left - ok
What happens occasionally (unexpected):
node2: set sync.wsrep_apply_cb in order to start waiting in the background INSERT
node1: INSERT start
node2 (background): INSERT start
node1: INSERT end
// The background INSERT still has _not_ reached the place where it starts
// waiting for the signal:
// DBUG_EXECUTE_IF("sync.wsrep_apply_cb", "now wait_for...");
node2: send signal to background INSERT: "stop waiting and continue executing"
node2: clear sync.wsrep_apply_cb as no longer needed
// The background INSERT reaches DBUG_EXECUTE_IF("sync.wsrep_apply_cb", ...)
// but sync.wsrep_apply_cb has already been cleared and the "wait" code is not
// executed. The signal remains unconsumed.
node2 (background): INSERT end
node2: DROP TABLE
node2: check no pending signals are left - failure, signal.wsrep_apply_cb is
pending (not consumed)
Remove MW-360 test case as it is not intended for MariaDB (uses
MySQL GTID).
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)
Change the semantics of thd_get_error_context_description().
It no longer expects the caller to lock LOCK_thread_count
(no caller ever did that anyway), but takes care of it internally.
This could happen when the client connection dies while sending a progress
report packet.
Fixed by not raising any errors when sending progress packets.
and
MDEV-13011 Server crashes in THD::handle_condition or Assertion `! is_set() || m_can_overwrite_status' fails upon attempt to connect with max_session_mem_used = 8192
errors when a connection is killed in the
* TABLE_SHARE::init_from_sql_statement_string()
* THD::init()
also, safety-wise, don't check max_mem_used on free() and when some error
was already issued.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
/home/travis/build/MariaDB/server/sql/sql_class.cc:1941:15: warning: 'this' pointer cannot be null in well-defined C++ code; pointer may be assumed to always convert to true [-Wundefined-bool-conversion]
if (this && WSREP(this) && wsrep_thd_is_BF(this, FALSE))
^~~~ ~~
because mysql->net.thd was reset to NULL in mysql_real_connect()
and thd_increment_bytes_received() didn't do anything.
Fix:
* set mysql->net.thd to current_thd instread.
* remove the test for non-null THD from a very often used
function thd_increment_bytes_received().
This is backport of WL#7195 to MySQL-5.5. In 5.5, we
offload connection authentication from the acceptor
thread to tp worker threads.
Connection authentication happens in the acceptor thread that
accepts the connection for thread pool plugin. Connection authentication
involves exchanging packets with client and disk I/O
which is time consuming. This can cause other client
connections to starve and wait in the queue possibly increasing the
connect latency and decreasing throughput. In the worst case, some
connections could be dropped. n addition, SSL handshakes are quite
expensive and can stall connections in the accept queue.
This patch offloads connection authentication when thread pool
plugin is used for client connection. Each thread group
shall have a queue of connection_context objects, which represents
new connections that need to be processed by thread group threads.
The connection context is composed of THD object & list pointers
for intrusive queue implementation. Whenever a new connection
arrives, connection context object is created and added to the
queue. A new connect handler thread is created or woken up to handle
the authentication task. The worker thread loop is modified to
process connection events on connect handler threads in addition to
checking for query processing events. The initial number of connect
handler threads is one per thread group and it is restricted to
a maximum of 4 threads per thread group.
it used current_thd->alloc() and allocated on the thd's execution arena,
not on table->expr_arena.
Remove THD::arena_for_cached_items that is temporarily set in
update_virtual_fields(), and replaces THD arena in get_datetime_value().
Instead set THD arena to table->expr_arena for the whole duration
of update_virtual_fields()
RESTRICTED IN ALL GA RELEASES
Back port of WL#6782 to 5.5 and 5.6. This also includes
back port of Bug#20771331, Bug#20741572 and Bug#20770671.
Bug#24695274 and Bug#24679907 are also handled along with
this.
When a deadlock kill is detected inside the storage engine, the kill
is not done immediately, to avoid calling back into the storage engine
kill_query method with various lock subsystem mutexes held. Instead the
kill is queued and done later by a slave background thread.
This patch in preparation for fixing TokuDB optimistic parallel
replication, as well as for removing locking hacks in InnoDB/XtraDB in
10.2.
Signed-off-by: Kristian Nielsen <knielsen at knielsen-hq.org>
In galera cluster, the definer (and thus binlog invoker) must be set
for CREATE ROLE before Query_log_event is created during TOI on the
originating node.
If a conflict happens under wsrep_on, the THD's wsrep_conflict_state
is typically set to MUST_ABORT and cleared later, when transaction is
aborted. However, when wsrep_on is disabled, no check is performed to
see whether wsrep_conflict_state is set. So this potentially creates
spurious deadlock errors on the subsequent statement that runs with
wsrep_on enabled.
To avoid this problem wsrep_thd_set_conflict_state() sets the conflict
state only if wsrep_on is enabled.
- reverted from tracking donor servicing thread. With xtrabackup SST,
xtrabackup thread will call FTWRL and node is desynced upfront
- Skipping desync in FTWRL if node is operating as donor
- enveloped FTWRL processing with wsrep desync/resync calls. This way FTWRL processing node
will not cause flow control to kick in
- donor servicing thread is unfortunate exception, we must let him to pause provider as part
of FTWRL phase, but not desync/resync as this is done as part of donor control on higher
level
