Reason : after running sysbench tests (rw,update_no_index), in all cases
the throughout was considerably (approx 15%) better with the patch removed.

Reverted commit info
commit 8dc03bee3ade2edcc53a3a257346f4a0a9f0b44c
Author: Yasufumi Kinoshita <yasufumi.kinoshita@oracle.com>
Date:   Wed Nov 20 17:02:24 2013 +0900

Bug #17824101 : WL#7050 CAUSES RW PERFORMANCE REGRESSION AT SOME WINDOWS ENVIRONMENT

InnoDB undo logs currently always use the innodb_page_size,
whether they are stored in the system tablespace, in a
dedicated undo tablespace, or in the temporary tablespace.
Remove redundant page_size parameters.

TrxUndoRsegsIterator::set_next(): return bool instead of page_size.

trx_rseg_mem_create(): Remove the parameter rseg_array.
Update trx_sys->rseg_array directly.

TrxUndoRsegsIterator::m_purge_sys: Remove. There is only one purge_sys.

purge_sys_t: Renamed from trx_purge_t. Define a constructor and
destructor. Allocate rseg_iter, purge_queue inline.

purge_sys->trx: Remove. Use purge_sys->sess->trx instead.

purge_sys->view_active: Remove. Access to purge_sys->view is always
protected by purge_sys->latch.

trx_purge_sys_create(): Replaced by purge_sys_t::purge_sys_t().

trx_purge_sys_close(): Replaced by purge_sys_t::~purge_sys_t().

Also in log_checkpoint(), where fil_flush_file_spaces() was
not done on Windows, it is not done.

 Remove srv_win_file_flush_method

- Rename srv_unix_file_flush_method to srv_file_flush_method, and
  rename constants to remove UNIX from them, i.e SRV_UNIX_FSYNC=>SRV_FSYNC

- Add SRV_ALL_O_DIRECT_FSYNC corresponding to current Windows default
(no buffering for either log or data, flush on both log and data)

- change os_file_open on Windows to behave identically to Unix wrt
O_DIRECT and O_DSYNC settings. map O_DIRECT to FILE_FLAG_NO_BUFFERING and
O_DSYNC to FILE_FLAG_WRITE_THROUGH

- remove various #ifdef _WIN32

MDEV-11363: Assertion `!derived->first_sel ect()->first_inner_unit() || derived->first_select()->first_inner_unit()->first_select()-> exclude_from_table_unique_test' failed in TABLE_LIST::set_check_materialized()

Do not try to materialize derived table which already merged (irreversebly).

InnoDB needs to collect transactions from the persistent data files
in trx_rseg_array_init() before trx_lists_init_at_db_start() is
executed. But there is no need to create purge_sys->purge_queue
separately from purge_sys.

trx_sys_init_at_db_start(): Change the return type to void.
Remove the direct call to trx_rseg_array_init(). It will be called
by trx_lists_init_at_db_start(), which we are calling.
Initialize the purge system read view.

trx_lists_init_at_db_start(): Call trx_purge_sys_create(), which will
invoke trx_rseg_array_init() to read the undo log segments.

trx_purge_sys_create(): Remove the parameters. Do not initialize
the purge system read view, because trx_sys->rw_trx_list has not
been recovered yet. The purge_sys->view will be initialized at
the end of trx_sys_init_at_db_start().

trx_rseg_array_init(): Remove the parameter. Use purge_sys->purge_queue
directly.

innobase_start_or_create_for_mysql(): Remove the local variable
purge_queue. Do not call trx_purge_sys_create(), because it will be
called by trx_sys_init_at_db_start().

In MySQL 5.7, there is some redundant code for supposedly handling
an upgrade from an earlier version of InnoDB.

An upgrade of InnoDB between major versions should include a
slow shutdown (innodb_fast_shutdown=0) of the previous version.

A comment in trx_lists_init_at_db_start() confused clean shutdown
and slow shutdown. A clean shutdown does not necessarily guarantee
that there are no active transactions. A slow shutdown guarantees
that.

Because there was no code to handle rollback of recovered transactions
that happened to use the rollback segment slots that MySQL 5.7.2
repurposed for temporary undo logs, the upgrade is not working in all
cases, and we may as well remove the code to handle purging.

trx_sys_t::pending_purge_rseg_array: Remove.

trx_undo_get_undo_rec_low(): Define as static. Remove the parameter
is_redo_rseg.

trx_undo_get_undo_rec(), trx_rseg_get_on_id(): Remove the parameter
is_redo_rseg.

trx_rseg_mem_free(): Remove the second parameter.

trx_sys_get_nth_rseg(): Replace with trx_rseg_get_on_id().

trx_rseg_schedule_pending_purge(): Remove.

Prepare os ANALYZE now respond as EXPLAIN.

This fixes some GCC 6.3.0 warnings and makes the code a little
more debugging-friendly.

After starting MariaDB 10.2 with an invalid value of
--innodb-flush-method= (the empty string), shutdown would
attempt to dereference some NULL pointers. This was probably broken
in commit 81b7fe9d which implemented
shutdown after aborted startup.

logs_empty_and_mark_files_at_shutdown(): Allow shutdown even if
lock_sys, log_sys, or fil_system is NULL.

os_aio_free(): Tolerate os_aio_segment_wait_events==NULL.

innobase_start_or_create_for_mysql(): Do not invoke
srv_init_abort() before initializing all mutexes for the temporary files.

innodb_shutdown(): Tolerate buf_pool_ptr==NULL.

Provide more useful progress reporting of crash recovery.

recv_sys_t::progress_time: The time of the last report.

recv_sys_t::report(ib_time_t): Determine whether progress should
be reported.

recv_scan_print_counter: Remove.

log_group_read_log_seg(): After after each I/O request, invoke
recv_sys_t::report() and report progress if needed.

recv_apply_hashed_log_recs(): Change the return type back to void
(DB_SUCCESS was always returned), and rename the parameter to last_batch.
At the start of each batch, if there are pages to be recovered,
issue a message.

MDEV-10704: Assertion `field->field->table == table_arg' failed in fill_record(THD*, TABLE*, List<Item>&, List<Item>&, bool, bool)

the bug test suite

Introduced 2f63e2e2

Compiler error was:

sql/log_event.cc: In function ‘size_t log_event_print_value(IO_CACHE*, const uchar*, uint, uint, char*, size_t)’:
sql/log_event.cc:2897:7: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
       if (!ptr)
       ^~
sql/log_event.cc:2900:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’
         int32 i32= uint2korr(ptr);
         ^~~~~

Added in 950abd52

Error was:

sql/item_sum.cc:3478:5: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
     if ((!args[i]->fixed &&
     ^~
/sql/item_sum.cc:3482:7: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’
       with_subselect|= args[i]->with_subselect;
       ^~~~~~~~~~~~~~
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

The bug was caused by a wrong order of statements in With_clause::print().
As a result any view definition containing WITH clause with several
CTE specifications was put the frm file in a syntactically incorrect
form.

Also get rid of example ini files, they do not provide any value,
just confusion

The InnoDB redo log record type MLOG_COMP_REC_SEC_DELETE_MARK has
been unused for a long time, and it has never been written after
WL#8845 introduced the redo log format identifier in MySQL 5.7.9
or MariaDB Server 10.2.2. Thus, removing the record type does not
constitute any functional change.

Define my_thread_id as an unsigned type, to avoid mismatch with
ulonglong.  Change some parameters to this type.

Use size_t in a few more places.

Declare many flag constants as unsigned to avoid sign mismatch
when shifting bits or applying the unary ~ operator.

When applying the unary ~ operator to enum constants, explictly
cast the result to an unsigned type, because enum constants can
be treated as signed.

In InnoDB, change the source code line number parameters from
ulint to unsigned type. Also, make some InnoDB functions return
a narrower type (unsigned or uint32_t instead of ulint;
bool instead of ibool).

To facilitate multiple build types in Travis, the environment variable
MYSQL_{BUILD_CC,BUILD_CXX} will be passed to cmake if used. This will
fallback to $CC/$CXX otherwise.

Added MYSQL_COMPILER_LAUNCHER (usually ccache) which isn't supported
until cmake-3.4, which isn't in travis (trusty), but hopefully a later
version can use it or in CI systems other than travis.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

Merge branch '10.2-MDEV-120555-test_binlog_stm_ctype_ucs' of https://github.com/grooverdan/mariadb-server into grooverdan-10.2-MDEV-120555-test_binlog_stm_ctype_ucs

The function thd_supports_xa() was removed in MySQL 5.7 in WL#8843.

Remove the unused variable innodb_calling_exit which was added
in MySQL 5.7 in an attempt to avoid failures in other threads when
an I/O thread calls exit().

Since MDEV-9282, InnoDB or XtraDB MariaDB Server is not calling
exit() at all, and the variable innodb_calling_exit was never set.

Because the default build configuration of the server will remain
at -DWITH_INNODB_AHI=ON, we want to test the instrumentation.

We make and revert the test adjustments in separate commits on purpose,
so that this commit can be easily reverted later if the default
build configuration is changed to -DWITH_INNODB_AHI=OFF.

The InnoDB adaptive hash index is sometimes degrading the performance of
InnoDB, and it is sometimes disabled to get more consistent performance.
We should have a compile-time option to disable the adaptive hash index.

Let us introduce two options:

OPTION(WITH_INNODB_AHI "Include innodb_adaptive_hash_index" ON)
OPTION(WITH_INNODB_ROOT_GUESS "Cache index root block descriptors" ON)

where WITH_INNODB_AHI always implies WITH_INNODB_ROOT_GUESS.

As part of this change, the misleadingly named function
trx_search_latch_release_if_reserved(trx) will be replaced with the macro
trx_assert_no_search_latch(trx) that will be empty unless
BTR_CUR_HASH_ADAPT is defined (cmake -DWITH_INNODB_AHI=ON).

We will also remove the unused column
INFORMATION_SCHEMA.INNODB_TRX.TRX_ADAPTIVE_HASH_TIMEOUT.
In MariaDB Server 10.1, it used to reflect the value of
trx_t::search_latch_timeout which could be adjusted during
row_search_for_mysql(). In 10.2, there is no such field.

Other than the removal of the unused column TRX_ADAPTIVE_HASH_TIMEOUT,
this is an almost non-functional change to the server when using the
default build options.

Some tests are adjusted so that they will work with both
-DWITH_INNODB_AHI=ON and -DWITH_INNODB_AHI=OFF. The test
innodb.innodb_monitor has been renamed to innodb.monitor
in order to track MySQL 5.7, and the duplicate tests
sys_vars.innodb_monitor_* are removed.

This fixes MySQL Bug#80788 in MariaDB 10.2.5.

When I made the InnoDB crash recovery more robust by implementing
WL#7142, I also introduced an extra redo log scan pass that can be
shortened.

This fix will slightly extend the InnoDB redo log format that I
introduced in MySQL 5.7.9 by writing the start LSN of the MLOG_CHECKPOINT
mini-transaction to the end of the log checkpoint page, so that recovery
can jump straight to it without scanning all the preceding redo log.

LOG_CHECKPOINT_END_LSN: At the end of the checkpoint page, the start LSN
of the MLOG_CHECKPOINT mini-transaction. Previously, these bytes were
written as 0.

log_write_checkpoint_info(), log_group_checkpoint(): Add the parameter
end_lsn for writing LOG_CHECKPOINT_END_LSN.

log_checkpoint(): Remember the LSN at which the MLOG_CHECKPOINT
mini-transaction is starting (or at which the redo log ends on
shutdown).

recv_init_crash_recovery(): Remove.

recv_group_scan_log_recs(): Add the parameter checkpoint_lsn.

recv_recovery_from_checkpoint_start(): Read LOG_CHECKPOINT_END_LSN
and if it is set, start the first scan from it instead of the
checkpoint LSN. Improve some messages and remove bogus assertions.

recv_parse_log_recs(): Do not skip DBUG_PRINT("ib_log") for some
file-level redo log records.

recv_parse_or_apply_log_rec_body(): If we have not parsed all redo
log between the checkpoint and the corresponding MLOG_CHECKPOINT
record, defer the check for MLOG_FILE_DELETE or MLOG_FILE_NAME records
to recv_init_crash_recovery_spaces().

recv_init_crash_recovery_spaces(): Refuse recovery if
MLOG_FILE_NAME or MLOG_FILE_DELETE records are missing.

This caused gcc-6.3.1 errors:7450cb7f

mariadb-server/sql/sql_base.cc: In function ‘bool fix_all_session_vcol_exprs(THD*, TABLE_LIST*)’:
mariadb-server/sql/sql_base.cc:4821:7: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation]
       for (Field **df= t->default_field; df && *df; df++)
       ^~~
mariadb-server/sql/sql_base.cc:4826:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘for’
         for (Virtual_column_info **cc= t->check_constraints; cc && *cc; cc++)
         ^~~

It was obvious from 7450cb7f that the indenting should of been removed
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

MDEV-7618 introduced configuration parameter innodb_instrument_semaphores
in MariaDB Server 10.1. The parameter seems to only affect the rw-lock
X-latch acquisition. Extra fields are added to rw_lock_t to remember one
X-latch holder or waiter. These fields are not being consulted or reported
anywhere. This is basically only adding code bloat.

If the intention is to debug hangs or deadlocks, we have better tools for
that in the debug server, and for the non-debug server, core dumps can
reveal a lot. For example, the mini-transaction memo records the
currently held buffer block or index rw-locks, to be released at
mtr_t::commit().

The configuration parameter innodb_instrument_semaphores will be
deprecated in 10.2.5 and removed in 10.3.0.

rw_lock_t: Remove the members lock_name, file_name, line, thread_id
which did not affect any output.

The field should have been removed when merging MySQL 5.7.9
to MariaDB 10.2.2 in commit 2e814d47.

to tables in the system tablespace

This is a regression caused by MDEV-11585, which accidentally
changed Tablespace::is_undo_tablespace() in an incorrect way,
causing the InnoDB system tablespace to be reported as a dedicated
undo tablespace, for which the change buffer is not applicable.

Tablespace::is_undo_tablespace(): Remove. There were only 2
calls from the function buf_page_io_complete(). Replace those
calls as appropriate.

Also, merge changes to tablespace import/export tests from
MySQL 5.7, and clean up the tests a little further, allowing
them to be run with any innodb_page_size.

Remove duplicated error injection instrumentation for the
import/export tests.  In MySQL 5.7, the error injection label
buf_page_is_corrupt_failure was renamed to
buf_page_import_corrupt_failure.

fil_space_extend_must_retry(): Correct a debug assertion
(tablespaces can be extended during IMPORT), and remove a
TODO comment about compressed temporary tables that was
already addressed in MDEV-11816.

dict_build_tablespace_for_table(): Correct a comment that
no longer holds after MDEV-11816, and assert that
ROW_FORMAT=COMPRESSED can only be used in .ibd files.

Note: At least one test is unstable, failing with the following:
./mtr --mysqld=--innodb-purge-threads=9 --big-test --no-reorder \
galera.galera_parallel_autoinc_largetrx galera.galera_var_slave_threads

The result difference is dependent on innodb_purge_threads.

buf_dump(): Correct the printf format passed to buf_dump_status()
to match the argument types.

Revert the changes to storage/xtradb. XtraDB is not being compiled
for 10.2. The unused copy that we have in the 10.2 branch is only
getting merges from 10.1.

Disable the test sys_vars.innodb_buffer_pool_dump_pct_function
because it is unstable on buildbot.

MDEV-11454: Make innodb_buffer_pool_dump_pct refer to the entire buffer pool size

copy-paste error