mtr_t::commit_files(): Renamed from mtr_t::commit_checkpoint().
Remove the redundant bool parameter, and instead use checkpoint_lsn=0
to indicate that no checkpoint marker should be written.

Redo log subsystem was decoupled from tablespace subsystem. It now manages file
descriptors for redo log files by itself.

FIL_TYPE_LOG: removed, code in various places was simplified

SRV_LOG_SPACE_FIRST_ID: renamed to SRV_SPACE_ID_UPPER_BOUND
  to better match its purpose. Code in various places was simplified

fil_n_log_flushes: replaced with log_sys::flushes
fil_n_pending_log_flushes: replaced with log_sys::pending_flushes

log_t::files::files: redo log file descriptors
log_t::files::file_names: redo log file names

log_t::files::set_file_names(): set file names without opening them
log_t::files::open_files(): opens redo log files
log_t::files::read(): treats several files as one big
log_t::files::write(): treats several files as one big
log_t::files::fsync(): flushes page cache to disk
log_t::files::close_files(): closes redo log files

fil_open_log_and_system_tablespace_files(): renamed to
  fil_open_system_tablespace_files()
  and obviously it now doesn't open redo log files

global files[1000]: removed. Why it was needed at all?

btr_cur_pessimistic_insert(): Relax a too strict debug assertion that
would fail when the function is invoked by btr_cur_pessimistic_update()
during innobase_add_instant_try(), that is, when updating the hidden
metadata record during a subsequent ADD COLUMN operation involves
splitting the leftmost clustered index leaf page.

This is a partial backport of 301bd62b
from 10.4.

Cause:
* row_start != 0 treated as it exists. Probably, possible row permutations had not been taken in mind.

Solution:
* Checking both row_start and row_end is correct, so versioned() function is used

MDEV-18875 Assertion `thd->transaction.stmt.ha_list == __null || trans == &thd->transaction.stmt' failed or bogus ER_DUP_ENTRY upon ALTER TABLE with versioning

Cause:
* when autocommit=0 (or transaction is issued by user),
 `ha_commit_trans` is called twice on ALTER TABLE, causing a duplicated
 insert into `transaction_registry` (ER_DUP_ENTRY).

Solution:
* ALTER TABLE makes an implicit commit by a second call. We actually
 need to make an insert only when it is a real commit. So is_real
 variable is additionally checked.

Instead of trying to detect MinProtocol=TLSv1.2 in all possible
sections of files in all possible locations where openssl is configured
to find its configuration in all possible distros (and these locations
are mutually different in Debian, Ubuntu, and RHEL, btw) - just make
mtr to instruct openssl not to read any config files at all.

This was broken since commit 193b5ed5

Removed hack with with_list

The function was only called by innobase_drop_tablespace(),
which was removed in commit 494e4b99
and added in commit 2e814d47.

The issue here is for degenerate joins we should execute the window
function but it is not getting executed in all the cases.

To get the window function values window function needs to be executed
always. This currently does not happen in few cases
where the join would return 0 or 1 row like
  1) IMPOSSIBLE WHERE
  2) MIN/MAX optimization
  3) EMPTY CONST TABLE

The fix is to make sure that window functions get executed
and the temporary table is setup for the execution of window functions

Also, suppress pcre2 warning, it is external project, its warnings should
not bother us.

Such CMake check is not relevant as the oldest supported gcc is 4.8 and
compiler issue was solved in gcc-4.6 already.
https://godbolt.org/z/7G64qo

cmp_data(): simplify code

innodb.cmake: restrict -fno-builtin-memcmp for GCC versions older that 4.6
where optimization issue was solved.

Add proper wait condition when provider options are restored.

Description:
============
To change 'CONSERVATIVE' @@global.slave_parallel_mode default to 'OPTIMISTIC'
in 10.5.

@sql/sys_vars.cc
Changed default parallel_mode to 'OPTIMISTIC'

@sql/rpl_filter.cc
Changed default parallel_mode to 'OPTIMISTIC'

@sql/mysqld.cc
Removed the initialization of 'SLAVE_PARALLEL_CONSERVATIVE' to
'opt_slave_parallel_mode' variable.

@mysql-test/suite/rpl/t/rpl_parallel_mdev6589.test
@mysql-test/suite/rpl/t/rpl_mdev6386.test
Added 'mtr' suppression to ignore 'ER_PRIOR_COMMIT_FAILED'. In case of
'OPTIMISTIC' mode if a transaction gets killed during "wait_for_prior_commit"
it results in above error "1964". Hence suppression needs to be added for this
error.

@mysql-test/suite/rpl/t/rpl_parallel_conflicts.test
Test has a 'slave.opt' which explicitly sets slave_parallel_mode to
'conservative'. When the test ends this mode conflicts with new default mode.
Hence check test case reports an error. The 'slave.opt' is removed and options
are set and reset within test.

@mysql-test/suite/multi_source/info_logs.result
@mysql-test/suite/multi_source/reset_slave.result
@mysql-test/suite/multi_source/simple.result
Result content mismatch in "show slave status" output. This is expected as new
slave_parallel_mode='OPTIMISTIC'.

@mysql-test/include/check-testcase.test
Updated default 'slave_parallel_mode' to 'optimistic'.

Refactored rpl_parallel.test into following test cases.
Test case 1: @mysql-test/suite/rpl/t/rpl_parallel_domain.test
Test case 2: @mysql-test/suite/rpl/t/rpl_parallel_domain_slave_single_grp.test
Test case 3: @mysql-test/suite/rpl/t/rpl_parallel_single_grpcmt.test
Test case 4: @mysql-test/suite/rpl/t/rpl_parallel_stop_slave.test
Test case 5: @mysql-test/suite/rpl/t/rpl_parallel_slave_bgc_kill.test
Test case 6: @mysql-test/suite/rpl/t/rpl_parallel_gco_wait_kill.test
Test case 7: @mysql-test/suite/rpl/t/rpl_parallel_free_deferred_event.test
Test case 8: @mysql-test/suite/rpl/t/rpl_parallel_missed_error_handling.test
Test case 9: @mysql-test/suite/rpl/t/rpl_parallel_innodb_lock_conflict.test
Test case 10: @mysql-test/suite/rpl/t/rpl_parallel_gtid_slave_pos_update_fail.test
Test case 11: @mysql-test/suite/rpl/t/rpl_parallel_wrong_exec_master_pos.test
Test case 12: @mysql-test/suite/rpl/t/rpl_parallel_partial_binlog_trans.test
Test case 13: @mysql-test/suite/rpl/t/rpl_parallel_ignore_error_on_rotate.test
Test case 14: @mysql-test/suite/rpl/t/rpl_parallel_wrong_binlog_order.test
Test case 15: @mysql-test/suite/rpl/t/rpl_parallel_incorrect_relay_pos.test
Test case 16: @mysql-test/suite/rpl/t/rpl_parallel_retry_deadlock.test
Test case 17: @mysql-test/suite/rpl/t/rpl_parallel_deadlock_corrupt_binlog.test
Test case 18: @mysql-test/suite/rpl/t/rpl_parallel_mode.test
Test case 19: @mysql-test/suite/rpl/t/rpl_parallel_analyze_table_hang.test
Test case 20: @mysql-test/suite/rpl/t/rpl_parallel_record_gtid_wakeup.test
Test case 21: @mysql-test/suite/rpl/t/rpl_parallel_stop_on_con_kill.test
Test case 22: @mysql-test/suite/rpl/t/rpl_parallel_rollback_assert.test

MDEV-21189 : Dropping partition with 'wsrep_OSU_method=RSU' and 'SESSION sql_log_bin = 0' cases the galera node to hang

Test cleanup. Best practice for using RSU, is to isolate the node
up-front, so this test did not reflect real world scenario

MDEV-21189 : Dropping partition with 'wsrep_OSU_method=RSU' and 'SESSION sql_log_bin = 0' cases the galera node to hang

Test cleanup. Best practice for using RSU, is to isolate the node
up-front, so this test did not reflect real world scenario

- post-push to fix the compilation issue

- Moved the recv_sys->heap memory condition inside recv_parse_log_recs().
So that, InnoDB can mark the status as STORE_NO earlier.

- InnoDB uses one third of buffer pool chunk size for reading the redo
log records. In that case, we can avoid the scenario where buffer ran
out of memory issue during recovery.

It's not safe to chenge the THD::thread_id.
So send the thread_id as an argument to the mysql_audit_external_lock.

item_cmpfunc.h includes pcre2.h, so with the bundled pcre2
it has to be built before anything that includes pcre2.h .
And item_cmpfunc.h is indirectly included everywhere,
also in many plugins.

Somehow Ninja and Makefiles generators can still deduce the
correct build dependencies, but Visual Studio generator cannot.

Two changes:
* move pcre2.h from item_cmpfunc.h to item_cmpfunc.cc
* create an explicit dependency on pcre2 for the server

Related changes in the server code.