Fix for v. 11.0

Fix for v. 10.11

Fix for v. 10.6

Fix for v. 10.5

Fix for v.11.0

 Fix for v.10.11

Fix for v. 10.6

In commit 24648768 (MDEV-30136)
the parameter innodb_flush_method was deprecated, with no direct
replacement for innodb_flush_method=O_DIRECT_NO_FSYNC.

Let us change innodb_doublewrite from Boolean to ENUM that can
be changed while the server is running:

OFF: Assume that writes of innodb_page_size are atomic
ON: Prevent torn writes (the default)
fast: Like ON, but avoid synchronizing writes to data files

The deprecated start-up parameter innodb_flush_method=NO_FSYNC will cause
innodb_doublewrite=ON to be changed to innodb_doublewrite=fast,
which will prevent InnoDB from making any durable writes to data files.
This would normally be done right before the log checkpoint LSN is updated.
Depending on the file systems being used and their configuration,
this may or may not be safe.

The value innodb_doublewrite=fast differs from the previous combination of
innodb_doublewrite=ON and innodb_flush_method=O_DIRECT_NO_FSYNC by always
invoking os_file_flush() on the doublewrite buffer itself
in buf_dblwr_t::flush_buffered_writes_completed(). This should be safer
when there are multiple doublewrite batches between checkpoints.
Typically, once per second, buf_flush_page_cleaner() would write out
up to innodb_io_capacity pages and advance the log checkpoint.
Also typically, innodb_io_capacity>128, which is the size of the
doublewrite buffer in pages. Should os_file_flush_func() not be invoked
between doublewrite batches, writes could be reordered in an unsafe way.

The setting innodb_doublewrite=fast could be safe when the doublewrite
buffer (the first file of the system tablespace) and the data files
reside in the same file system.

This was tested by running "./mtr --rr innodb.alter_kill". On the first
server startup, with innodb_doublewrite=fast, os_file_flush_func()
would only be invoked on the ibdata1 file and possibly ib_logfile0.
On subsequent startups with innodb_doublewrite=OFF, os_file_flush_func()
will be invoked on the individual data files during log_checkpoint().

Note: The setting debug_no_sync (in the code, my_disable_sync) would
disable all durable writes to InnoDB files, which would be much less safe.

IORequest::Type: Introduce special values WRITE_DBL and PUNCH_DBL
for asynchronous writes that are submitted via the doublewrite buffer.
In this way, fil_space_t::use_doublewrite() or buf_dblwr.in_use()
will only be consulted during buf_page_t::flush() and the doublewrite
buffer can be enabled or disabled without any fear of inconsistency.

buf_dblwr_t::block_size: Replaces block_size().

buf_dblwr_t::flush_buffered_writes(): If !in_use() and the doublewrite
buffer is empty, just invoke fil_flush_file_spaces() and return. The
doublewrite buffer could have been disabled while a batch was in
progress.

innodb_init_params(): If innodb_flush_method=O_DIRECT_NO_FSYNC,
set innodb_doublewrite=fast or innodb_doublewrite=fearless.

Thanks to Mark Callaghan for reporting this, and Vladislav Vaintroub
for feedback.

Original problem was error when configuring without initialized
submodule Columnstore:

  The source directory

    /home/midenok/src/mariadb/10.6c/src/storage/columnstore/columnstore

  does not contain a CMakeLists.txt file.

The original fix disabled Columnstore build when PLUGIN_COLUMNSTORE
was not defined, but this seems to be wrong and any plugin should be
built if it is not explicitly disabled. This is expected by buildbots.

Thanks to Vladislav Vaintroub <vvaintroub@gmail.com> for the fix

In mysql_install_db_win_admin test, dump bootstrap output in case of
bootstrap failure.

CMake doesn't set ${PLUGIN_COLUMNSTORE} to anything.

Delayed_insert has its own THD (initialized at mysql_insert()) and
hence its own LEX. Delayed_insert initalizes a very few parameters for
LEX and 'duplicates' is not in this list. Now we copy this missing
parameter from parser LEX (as well as sql_command).

MDEV-31903 Server crashes in _ma_reset_history upon UNLOCK table with auto-create history partitions

When INSERT does auto-create for t1 all its handler instances are
closed by alter_close_table(). At this time down the stack
maria_close() clears share->state_history. Later when we unlock the
tables Aria transaction manager accesses old share instance (the one
before t1 was closed) and tries to reset its state_history.

The problem is maria_close() didn't remove table from transaction's
list (used_tables). The fix does _ma_remove_table_from_trnman() which
is triggered by HA_EXTRA_PREPARE_FOR_RENAME.

Some fixes related to commit f838b2d7 and
Rows_log_event::do_apply_event() and Update_rows_log_event::do_exec_row()
for system-versioned tables were provided by Nikita Malyavin.
This was required by test versioning.rpl,trx_id,row.

The mini-benchmark.sh script failed to run in the latest Fedora
distributions in GitLab CI. Executing the benchmark inside a Docker
container had failed because the check for `perf` was done in a way that
caused the benchmark to exit because of the `set -e` option. Test and
skip `perf` to allowing the remaining benchmark activities to proceed.

This check was added in acb6684 but inadvertantly reverted in 42a1f94.

Logic was corrected to only run perf when the flag is enabled, and to
prevent perf stat and perf record from being simultaneously enabled.

Set -ex is also added to enable easier identification of mini-benchmark
issues in the future.

All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.

Item_func_group_concat::print() did not take into account
that Item_func_group_concat::separator can be of a different character set
than the "String *str" (when the printing is being done to).
Therefore, printing did not work correctly for:
- non-ASCII separators when GROUP_CONCAT is done on 8bit data
  or multi-byte data with mbminlen==1.
- all separators (even including simple ones like comma)
  when GROUP_CONCAT is done on ucs2/utf16/utf32 data (mbminlen>1).

Because of this problem, VIEW definitions did not print correctly to
their FRM files. This later led to a wrong SELECT and SHOW CREATE output.

Fix:

- Adding new String methods:

  bool append_for_single_quote_using_mb_wc(const char *str, size_t length,
                                           CHARSET_INFO *cs);

  bool append_for_single_quote_opt_convert(const char *str,
                                           size_t length,
                                           CHARSET_INFO *cs)

  which perform both escaping and character set conversion at the same time.

- Adding a new String method escaped_wc_for_single_quote(),
  to reuse the code between the old and the new methods.

- Fixing Item_func_group_concat::print() to use the new
  method append_for_single_quote_opt_convert().

innodb_log_spin_wait_delay_update(): Always acquire log_sys.latch
to protect the change of mtr_t::spin_wait_delay.

log_t::lock_lsn(): In the general case, actually use
mtr_t::spin_wait_delay as it was intended. In the x86 specific
log_t::lock_lsn_bts() we used mtr_t::spin_wait_delay.

Queries that select concatenated constant strings now have
colname and value that match.  For example,
  SELECT '123' 'x';
will return a result where the column name and value both
are '123x'.

Review: Daniel Black

.. even with MDEV-9095 fix

CapabilityBounding sets require filesystem setcap attributes
for the executable to gain privileges during execution.

A side effect of this however is the getauxvec(AT_SECURE) gets
set, and the secure_getenv from OpenSSL internals on
OPENSSL_CONF environment variable will get ignored (openssl gh issue
21770).

According to capabilities(7), Ambient capabilities don't trigger
ld.so triggering the secure execution mode.

Include SELinux and Apparmor capabilities for ipc_lock

This was the orginal implementation that reverted with a bunch of
commits.

This reverts commit a13e521b.

Revert "cmake: append to the array correctly"
This reverts commit 51e3f1da.

Revert "build failure with cmake < 3.10"
This reverts commit 49cf702e.

Revert "MDEV-33301 memlock with systemd still not working"
This reverts commit 8a1904d7.

We should not set debug sync point when holding a mutex
to avoid mutex ordering failure.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

User transactions may acquire explicit MDL locks from InnoDB level
when persistent statistics is re-read for a table.
If such a transaction would be subject to BF-abort, it was improperly
detected as a system transaction and wouldn't get aborted.

The fix: Check if a transaction holding explicit MDL locks is a user
transaction in the MDL conflict handling code.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

Add "real ip:<ip_or_localhost>" part to the aborted message
Only for proxy-protocoled connection, so it does not  not to cause
confusion to normal users.

Problem is that not all conflicting transactions have THD object.
Therefore, it must be checked that victim has THD
before it's identification is added to victim list as victim's
thread identification is later requested using thd_get_thread_id
function that requires that we have valid pointer to THD object
in trx->mysql_thd.

Victim might not have trx->mysql_thd in two cases:

(1) An incomplete transaction that was recovered from undo logs
on server startup (and not yet rolled back).

(2) Transaction that is in XA PREPARE state and whose client
connection was disconnected.

Neither of these can complete before lock_wait_wsrep()
releases lock_sys.latch.

(1) trx_t::commit_in_memory() is clearing both
trx_t::state and trx_t::is_recovered before it invokes
lock_release(trx_t*) (which would be blocked by the exclusive
lock_sys.latch that we are holding here). Hence, it is not
possible to write a debug assertion to document this scenario.

(2) If is in XA PREPARE state, it would eventually be rolled
back and the lock conflict would be resolved when an XA COMMIT
or XA ROLLBACK statement is executed in some other connection.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

.. is not updating some system tables

Some schema changes from MDEV-24312 master_host has 60 character limit, increase to 255 bytes
failed to happen in the upgrade for tables in the mysql schema:
* mysql.global_priv
* mysql.procs_priv
* mysql.proxies_priv
* mysql.roles_mapping

The necessary corrections have been made to the results file
for the wsrep_provider_plugin_defaults test, which are necessary
due to the update of the galera library & wsrep-lib.

MDEV-32787 : Assertion `!wsrep_has_changes(thd) || (thd->lex->sql_command == SQLCOM_CREATE_TABLE && !thd->is_current_stmt_binlog_format_row()) || thd->wsrep_cs().transaction().state() == wsrep::transaction::s_aborted' failed in void wsrep_commit_empty(THD*, bool)

When we commit empty transaction we should allow wsrep
transaction to be on s_must_replay state for DDL that
was killed during certification.

Fix is tested with RQG because deterministic mtr-testcase
was not found.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

MONITOR_INC_VALUE_CUMULATIVE is a multiline macro, so the second statement
will be executed always, regardless of "if" condition.

These problems first started with
commit b1ab211d (MDEV-15053).

Thanks to Yury Chaikou from ServiceNow for the report.

From the correctness point of view, it should be safe to release
all locks on index records that were not modified by the transaction.
Doing so should make the locks after XA PREPARE fully compatible
with what would happen if the server were restarted: InnoDB table
IX locks and exclusive record locks would be resurrected based on
undo log records.

Concurrently running transactions that are waiting for a lock may invoke
lock_rec_convert_impl_to_expl() to create an explicit record lock object
on behalf of the lock-owning transaction so that they can attaching
their waiting lock request on the explicit record lock object. Explicit
locks would be released by trx_t::release_locks() during commit or
rollback.

Any clustered index record whose DB_TRX_ID belongs to a transaction that
is in active or XA PREPARE state will be implicitly locked by that
transaction. On XA PREPARE, we can release explicit exclusive locks on
records whose DB_TRX_ID does not match the current transaction identifier.

lock_rec_unlock_unmodified(): Release record locks that are not implicitly
held by the current transaction.

lock_release_on_prepare_try(), lock_release_on_prepare():
Invoke lock_rec_unlock_unmodified().

row_trx_id_offset(): Declare non-static.

lock_rec_unlock(): Replaces lock_rec_unlock_supremum().

Reviewed by: Vladislav Lesin

By design, InnoDB has always hung when permanently running out of
buffer pool, for example when several threads are waiting to allocate
a block, and all of the buffer pool is buffer-fixed by the active threads.

The hang that we are fixing here occurs when the buffer pool is only
temporarily running out and the situation could be rescued by writing out
some dirty pages or evicting some clean pages.

buf_LRU_get_free_block(): Simplify the way how we wait for
the buf_flush_page_cleaner thread. This fixes occasional hangs
of the test encryption.innochecksum that were introduced by
commit a55b951e (MDEV-26827).
To play it safe, we use a timed wait when waiting for the
buf_flush_page_cleaner() thread to perform its job. Should that
thread get stuck, we will invoke buf_pool.LRU_warn() in order to
display a message that pages could not be freed, and keep trying
to wake up the buf_flush_page_cleaner() thread.

The INFORMATION_SCHEMA.INNODB_METRICS counters
buffer_LRU_single_flush_failure_count and
buffer_LRU_get_free_waits will be removed.
The latter is represented by buffer_pool_wait_free.

Also removed will be the message
"InnoDB: Difficult to find free blocks in the buffer pool"
because in d34479dc we
introduced a more precise message
"InnoDB: Could not free any blocks in the buffer pool"
in the buf_flush_page_cleaner thread.

buf_pool_t::LRU_warn(): Issue the warning message that we could
not free any blocks in the buffer pool. This may also be invoked
by buf_LRU_get_free_block() if buf_flush_page_cleaner() appears
to be stuck.

buf_pool_t::n_flush_dec(): Remove.

buf_pool_t::n_flush_dec_holding_mutex(): Rename to n_flush_dec().

buf_flush_LRU_list_batch(): Increment the eviction counter for blocks
of temporary, discarded or dropped tablespaces.

buf_flush_LRU(): Make static, and remove the constant parameter
evict=false. The only caller will be the buf_flush_page_cleaner()
thread.

IORequest::is_LRU(): Remove. The only case of evicting pages on
write completion will be when we are writing out pages of the
temporary tablespace. Those pages are not in buf_pool.flush_list,
only in buf_pool.LRU.

buf_page_t::flush(): Remove the parameter evict.

buf_page_t::write_complete(): Change the parameter "bool temporary"
to "bool persistent" and add a parameter for an already read state().

Reviewed by: Debarun Banerjee

The log_sys.lsn_lock is a very contended resource with a small
critical section in log_sys.append_prepare(). On many processor
microarchitectures, replacing the system call based log_sys.lsn_lock
with a pure spin lock would fare worse during high concurrency workloads,
wasting a significant amount of CPU cycles in the spin loop.

On other microarchitectures, we would see a significant amount of time
being spent in native_queued_spin_lock_slowpath() in the Linux kernel,
plus context switching between user and kernel address space. This was
pointed out by Steve Shaw from Intel Corporation.

Depending on the workload and the hardware implementation, it may be
useful to use a pure spin lock in log_sys.append_prepare().
We will introduce a parameter. The statement

	SET GLOBAL INNODB_LOG_SPIN_WAIT_DELAY=50;

would enable a spin lock that will execute that many MY_RELAX_CPU()
operations (such as the x86 PAUSE instruction) between successive
attempts of acquiring the spin lock. The use of a system call based
log_sys.lsn_lock (which is the default setting) can be enabled by

	SET GLOBAL INNODB_LOG_SPIN_WAIT_DELAY=0;

This patch will also introduce #ifdef LOG_LATCH_DEBUG
(part of cmake -DWITH_INNODB_EXTRA_DEBUG=ON) for more accurate
tracking of log_sys.latch ownership and reorganize the fields of
log_sys to improve the locality of reference and to reduce the
chances of false sharing.

When a spin lock is being used, it will be maintained in the
most significant bit of log_sys.buf_free. This is useful, because that is
one of the fields that is covered by the lock. For IA-32 or AMD64, we
implement the spin lock specially via log_t::lsn_lock_bts(), employing the
i386 LOCK BTS instruction. A straightforward std::atomic::fetch_or() would
translate into an inefficient loop around LOCK CMPXCHG.

mtr_t::spin_wait_delay: The value of innodb_log_spin_wait_delay.

mtr_t::finisher: Pointer to the currently used mtr_t::finish_write()
implementation. This allows to avoid introducing conditional branches.
We no longer invoke log_sys.is_pmem() at the mini-transaction level,
but we would do that in log_write_up_to().

mtr_t::finisher_update(): Update finisher when spin_wait_delay is
changed from or to 0 (the spin lock is changed to log_sys.lsn_lock or
vice versa).

When using semi-sync replication with
rpl_semi_sync_master_wait_point=AFTER_COMMIT, the performance of the
primary can significantly reduce compared to AFTER_SYNC's
performance for workloads with many concurrent users executing
transactions. This is because all connections on the primary share
the same cond_wait variable/mutex pair, so any time an ACK is
received from a replica, all waiting connections are awoken to check
if the ACK was for itself, which is done in mutual exclusion.

This patch changes this such that the waiting THD will use its own
local condition variable, and the ACK receiver thread only signals
connections which have been ACKed for wakeup. That is, the
THD::LOCK_wakeup_ready condition variable is re-used for this
purpose, and the Active_tranx queue nodes are extended to hold the
waiting thread, so it can be signalled once ACKed.

Additionally:

 1)  Removed part of MDEV-11853 additions, which allowed suspended
connection threads awaiting their semi-sync ACKs to live until their
ACKs had been received. This part, however, wasn't needed.  That is,
all that was needed was for the Ack_thread to survive.  So now the
connection threads are killed during phase 1. Thereby
THD::is_awaiting_semisync_ack, and all its related code was removed.

 2) COND_binlog_send is repurposed to signal on the condition when
Active_tranx is emptied during clear_active_tranx_nodes.

 3) At master shutdown (when waiting for slaves), instead of the
main loop individually waiting for each ACK, await_slave_reply()
(renamed await_all_slave_replies()) just waits once for the
repurposed COND_binlog_send to signal it is empty.

 4) Test rpl_semi_sync_shutdown_await_ack is updates as following:
   4.1) Added test case (adapted from Kristian Nielsen) to ensure
that if a thread awaiting its ACK is killed while SHUTDOWN WAIT FOR
ALL SLAVES is issued, the primary will still wait for the ACK from
the killed thread.
   4.2) As connections which by-passed phase 1 of thread killing no
longer are delayed for kill until phase 2, we can no longer query
yes/no tx after receiving an ACK/timeout. The check for these
variables is removed.
   4.3) Comment descriptions are updated which mention that the
connection is alive; and adjusted to be the Ack_thread.

Reviewed By:
============
Kristian Nielsen <knielsen@knielsen-hq.org>