(Variant 2b: call greedy_search() twice, correct handling for limited
 search_depth)

Modify the join optimizer to specifically try to produce join orders that
can short-cut their execution for ORDER BY..LIMIT clause.

The optimization is controlled by @@optimizer_join_limit_pref_ratio.
Default value 0 means don't construct short-cutting join orders.
Other value means construct short-cutting join order, and prefer it only
if it promises speedup of more than #value times.

In Optimizer Trace, look for these names:
* join_limit_shortcut_is_applicable
* join_limit_shortcut_plan_search
* join_limit_shortcut_choice

Added comments
Moved a part into find_indexes_matching_order().

Replication of MyISAM and Aria DML is experimental and best
effort only. Earlier change make INSERT SELECT on both
MyISAM and Aria to replicate using TOI and STATEMENT
replication. Replication should happen only if user
has set needed wsrep_mode setting.

Note: This commit contains additional changes compared
to those already made for the 10.5 branch.

+ small refactoring after main fix.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

It's possible that MDL conflict handling code is called more
than once for a transaction when:
- it holds more than one conflicting MDL lock
- reschedule_waiters() is executed,
which results in repeated attempts to BF-abort already aborted
transaction.
In such situations, it might be that BF-aborting logic sees
a partially rolled back transaction and erroneously decides
on future actions for such a transaction.

The specific situation tested and fixed is when a SR transaction
applied in the node gets BF-aborted by a started TOI operation.
It's then caught with the server transaction already rolled back,
but with no MDL locks yet released. This caused wrong state
detection for such a transaction during repeated MDL conflict
handling code execution.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

* Fixes galera.galera_bf_kill_debug test case.
* Enable galera_ssl_upgrade, galera_ssl_reload, galera_pc_bootstrap
* Add MDEV to disabled tests that miss it

P.S. This commit contains additional changes compared
to the similar commit for 10.5 branch.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

After closing https://github.com/codership/galera-bugs/issues/947,
Galera now correctly certifies table-level keys, which made bulk
insert work again.

The corresponding MTR test is made deterministic and re-enabled.

Requires Galera 26.4.19
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

* Fixes galera.galera_bf_kill_debug test case.
* Enable galera_ssl_upgrade, galera_ssl_reload, galera_pc_bootstrap
* Add MDEV to disabled tests that miss it
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

Based on logs SST was started before donor reached
Primaty state. Add wait_conditions to make sure that
nodes reach Primary state before starting next node.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

generate consistent error messages,
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

For TOI events specifically we have a situation where in case of the
same error different nodes may generate different messages. This may
be for two reasons:
 - different locale setting between the current client session and
   server default (we can reasonably require server locales to be
   identical on all nodes, but user can change message locale for the
   session)
 - non-deterministic course of STATEMENT execution e.g. for ALTER TABLE

On the other hand we may reasonably expect TOI event failures since
they are executed after replication, so we must ensure that voting is
consistent. For that purpose error codes should be sufficiently unique
and deterministic for TOI event failures as DDLs normally deal with
a single object, so we can merely use MySQL error codes to vote on.

Notice that this problem does not happen with regular transactional
writesets, since the originator node will always vote success and
replica nodes are assumed to have the same global locale setting.
As such different error messages indicate different errors even if
the error code is the same (e.g. ER_DUP_KEY can happen on different
rows tables).

Use only MySQL error code (without the error message) for error voting
in case of TOI event failure.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

error condition (SST failure), so it should set error code before
exiting.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

use grep with -a option.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

When handling fatal signal, shut down Galera networking
before printing out stack trace and writing core file.
This is to achieve fail-silent semantics on crashes which may
keep the process running for a long time, but not fully responding
e.g. due to core dumping or symbol resolving.

Also suppress all Galera/wsrep logging to avoid logging from
background threads to garble crash information from signal handler.

Notice that for fully fail-silent crash, Galera 26.4.19 is needed.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

This bug was fixed by the patch for bug MDEV-26402.
Only a test case that failed before this patch was applied is added
in this commit.

MDEV-31173 : Server crashes when setting wsrep_cluster_address after adding invalid value to wsrep_allowlist table

Problem was that wsrep_schema tables were not marked as
category information. Fix allows access to wsrep_schema
tables even when node is detached.

This is 10.4-10.9 version of fix.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

MDEV-33997 : Assertion `((WSREP_PROVIDER_EXISTS_ && this->variables.wsrep_on) && wsrep_emulate_bin_log) || mysql_bin_log.is_open()' failed in int THD::binlog_write_row(TABLE*, bool, const uchar*)

Problem was that we did not found that table was partitioned
and then we should find what is actual underlaying storage
engine.

We should not use RSU for !InnoDB tables.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

Fix MDEV-34704 typos.

Added missing method of Item_static_float_func

  --quick-max-column-width parameter added to limit field
    width in --quick mode.

recv_recovery_from_checkpoint_start(): Abort startup due to log
corruption if we were unable to parse the entire log between
the latest log checkpoint and the corresponding FILE_CHECKPOINT record.

Also, reduce some code bloat related to log output and log_sys.mutex.

Reviewed by: Debarun Banerjee

In commit fa8a46eb (MDEV-33613)
the parameter innodb_lru_flush_size ceased to have any effect.

Let us declare the parameter as deprecated and additionally as
MARIADB_REMOVED_OPTION, so that there will be a warning written
to the error log in case the option is specified in the command line.

Let us also do the same for the parameter
innodb_purge_rseg_truncate_frequency
that was deprecated&ignored earlier in MDEV-32050.

Reviewed by: Debarun Banerjee

Let us avoid EXTENDED in the CHECK TABLE after a defragmentation,
because it would occasionally report an orphan delete-marked record
in the index "third". That error does not seem to be reproducible
when using the regular OPTIMIZE TABLE.

Also, let us make the test --repeat safe by removing the defragmentation
related statistics after DROP TABLE.

The defragmentation feature was removed in later releases in
commit 7ca89af6 (MDEV-30545)
along with this test case.

Also restored a change that resulted in off-by-one, as well as
appending the correctly indexed key_hint.

purge_sys_t::stop_FTS(): Fix an incorrect debug assertion that
commit d58734d7 added.
The assertion would fail if there had been prior invocations of
purge_sys.stop_SYS() without purge_sys.resume_SYS().
The intention of the assertion is to check that number of pending
stop_FTS() stays below 65536.

The test was expecting the I/O thread to be in a specific state, but thread
scheduling may cause it to not yet have reached that state. So just have a
loop that waits for the expected state to occur.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Remove the test for MDEV-14528. This is supposed to test that parallel
replication from pre-10.0 master will update Seconds_Behind_Master. But
after MDEV-12179 the SQL thread is blocked from even beginning to fetch
events from the relay log due to FLUSH TABLES WITH READ LOCK, so the test
case is no longer testing what is was intended to. And pre-10.0 versions are
long since out of support, so does not seem worthwhile to try to rewrite the
test to work another way.

The root cause of the test failure is MDEV-34778. Briefly, depending on
exact timing during slave stop, the rli->sql_thread_caught_up flag may end
up with different value. If it ends up as "true", this causes
Seconds_Behind_Master to be 0 during next slave start; and this caused test
case timeout as the test was waiting for Seconds_Behind_Master to become
non-zero.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Depending on timing, an extra event run could start just when the event
scheduler is shut down and delay running until after the table has been
dropped; this would cause the test to fail with a "table does not exist"
error in the log.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

(Revert a change done by mistake when XtraDB was removed.)
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Before doing mark_start_commit(), check that there is no pending deadlock
kill. If there is a pending kill, we won't commit (we will abort, roll back,
and retry). Then we should not mark the commit as started, since that could
potentially make the following GCO start too early, before we completed the
commit after the retry.

This condition could trigger in some corner cases, where InnoDB would take
temporarily table/row locks that are released again immediately, not held
until the transaction commits. This happens with dict_stats updates and
possibly auto-increment locks.

Such locks can be passed to thd_rpl_deadlock_check() and cause a deadlock
kill to be scheduled in the background. But since the blocking locks are
held only temporarily, they can be released before the background kill
happens. This way, the kill can be delayed until after mark_start_commit()
has been called. Thus we need to check the synchronous indication
rgi->killed_for_retry, not just the asynchroneous thd->killed.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Before this patch, the InnoDB purge coordinator task submitted
innodb_purge_threads-1 tasks even if there was not sufficient amount
of work for all of them. For example, if there are undo log records
only for 1 table, only 1 task can be employed, and that task had better
be the purge coordinator.

srv_purge_worker_task_low(): Split from purge_worker_callback().

trx_purge_attach_undo_recs(): Remove the parameter n_purge_threads,
and add the parameter n_work_items, to keep track of the amount of
work.

trx_purge(): Launch purge worker tasks only if necessary. The work of
one thread will be executed by this purge coordinator thread.

que_fork_scheduler_round_robin(): Merged to trx_purge().

Thanks to Vladislav Vaintroub for supplying a prototype of this.

Reviewed by: Debarun Banerjee

In a Sysbench oltp_update_index workload that involves 1 table,
a serious contention between the workload and the purge of history
was observed. This was the worst when the table contained only 1 record.

This turned out to be fixed by setting innodb_purge_batch_size=128,
which corresponds to the number of usable persistent rollback segments.
When we go above that, there would be contention between row_purge_poss_sec()
and the workload, typically on the clustered index page latch, sometimes
also on a secondary index page latch. It might be that with smaller
batches, trx_sys.history_size() will end up pausing all concurrent
transaction start/commit frequently enough so that purge will be able
to make some progress, so that there would be less contention on the
index page latches between purge and SQL execution.

In commit aa719b50 (part of MDEV-32050)
the interpretation of the parameter innodb_purge_batch_size was slightly
changed. It would correspond to the maximum desired size of the
purge_sys.pages cache. Before that change, the parameter was referring to
a number of undo log pages, but the accounting might have been inaccurate.

To avoid a regression, we will reduce the default value to
innodb_purge_batch_size=127, which will also be compatible with
innodb_undo_tablespaces>1 (which will disable rollback segment 0).

Additionally, some logic in the purge and MVCC checks is simplified.
The purge tasks will make use of purge_sys.pages when accessing undo
log pages to find out if a secondary index record can be removed.
If an undo page needs to be looked up in buf_pool.page_hash, we will
merely buffer-fix it. This is correct, because the undo pages are
append-only in nature. Holding purge_sys.latch or purge_sys.end_latch
or the fact that the current thread is executing as a part of an
in-progress purge batch will prevent the contents of the undo page from
being freed and subsequently reused. The buffer-fix will prevent the
page from being evicted form the buffer pool. Thanks to this logic,
we can refer to the undo log record directly in the buffer pool page
and avoid copying the record.

buf_pool_t::page_fix(): Look up and buffer-fix a page. This is useful
for accessing undo log pages, which are append-only by nature.
There will be no need to deal with change buffer or ROW_FORMAT=COMPRESSED
in that case.

purge_sys_t::view_guard::view_guard(): Allow the type of guard to be
acquired: end_latch, latch, or no latch (in case we are a purge thread).

purge_sys_t::view_guard::get(): Read-only accessor to purge_sys.pages.

purge_sys_t::get_page(): Invoke buf_pool_t::page_fix().

row_vers_old_has_index_entry(): Replaced with row_purge_is_unsafe()
and row_undo_mod_sec_unsafe().

trx_undo_get_undo_rec(): Merged to trx_undo_prev_version_build().

row_purge_poss_sec(): Add the parameter mtr and remove redundant
or unused parameters sec_pcur, sec_mtr, is_tree. We will use the
caller's mtr object but release any acquired page latches before
returning.

btr_cur_get_page(), page_cur_get_page(): Do not invoke page_align().

row_purge_remove_sec_if_poss_leaf(): Return the value of PAGE_MAX_TRX_ID
to be checked against the page in row_purge_remove_sec_if_poss_tree().
If the secondary index page was not changed meanwhile, it will be
unnecessary to invoke row_purge_poss_sec() again.

trx_undo_prev_version_build(): Access any undo log pages using
the caller's mini-transaction object.

row_purge_vc_matches_cluster(): Moved to the only compilation unit that
needs it.

Reviewed by: Debarun Banerjee

There were two separate Atomic_counter<uint32_t>, purge_sys.m_SYS_paused
and purge_sys.m_FTS_paused. In purge_sys.wait_FTS() we have to read both
atomically. We used to use an overkill solution for this, acquiring
purge_sys.latch and waiting 10 milliseconds between samples. To make
matters worse, the 10-millisecond wait was unconditional, which would
unnecessarily suspend the purge_coordinator_task every now and then.

It turns out that we can fold both "reference counts" into a single
Atomic_relaxed<uint32_t> and avoid the purge_sys.latch.
To assess whether std::memory_order_relaxed is acceptable, we should
consider the operations that read these "reference counts", that is,
purge_sys_t::wait_FTS(bool) and purge_sys_t::must_wait_FTS().

Outside debug assertions, purge_sys.must_wait_FTS() is only invoked in
trx_purge_table_acquire(), which is covered by a shared dict_sys.latch.
We would increment the counter as part of a DDL operation, but before
acquiring an exclusive dict_sys.latch. So, a
purge_sys_t::close_and_reopen() loop could be triggered slightly
prematurely, before a problematic DDL operation is actually executed.
Decrementing the counter is less of an issue; purge_sys.resume_FTS()
or purge_sys.resume_SYS() would mostly be invoked while holding an
exclusive dict_sys.latch; ha_innobase::delete_table() does it outside
that critical section. Still, this would only cause some extra wait in
the purge_coordinator_task, just like at the start of a DDL operation.

There are two calls to purge_sys_t::wait_FTS(bool): in the above mentioned
purge_sys_t::close_and_reopen() and in purge_sys_t::clone_oldest_view(),
both invoked by the purge_coordinator_task. There is also a
purge_sys.clone_oldest_view<true>() call at startup when no DDL operation
can be in progress.

purge_sys_t::m_SYS_paused: Merged into m_FTS_paused, using a new
multiplier PAUSED_SYS = 65536.

purge_sys_t::wait_FTS(): Remove an unnecessary sleep as well as the
access to purge_sys.latch. It suffices to poll purge_sys.m_FTS_paused.

purge_sys_t::stop_FTS(): Do not acquire purge_sys.latch.

Reviewed by: Debarun Banerjee