[Adjusting Sergei Krivonos's patch]

"duplicates_removal" may contain multiple elements inside it and
so should have a JSON array as a value (and not object).

This reverts commit 2d21917e.

No explainations, lots of code moved, wrong cmake changes

This reverts commit 9feaa6be.

No, we do NOT support fmt 6.x, it formats values differently.
And we MUST use FMT_HEADER_ONLY

Signed-off-by: Sergei Krivonos <sergei.krivonos@mariadb.com>

page_zip_des_t::clear(): Avoid a bogus GCC warning with
some pointer arithmetics. Yes, storing the unrelated member "fix"
in this object is ugly, but it avoids memory alignment overhead
on 64-bit architectures.

In commit aae3f921
recv_apply_hashed_log_recs() was replaced by recv_sys_t::apply().

log_write_buf(): do not cast to size_t which prevents to write to files
which a bigger that 4G and remove useless assertion

A part of the test main.long_unique attempts to insert records
with two 60,000,001-byte columns. Let us move that test into
a separate file main.long_unique_big, declared as big test,
so that it can be skipped in environments with limited memory.

How 'bout know?

Hi,

if the pid-file option is configured more than once (e.g. multiple times in different files), my_print_defaults prints it twice, resulting in the logrotate postrotate script failing because of a syntax error. Debian fixed this already (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=830976#42).

Perhaps you could implement this small change in the other branches as well?

Thanks,

Christopher

Several EXTENDED type records have already been implemented.

- Replaced the pointer parameter of validate_for_recovery() with uint32_t

* galera_kill_applier : we should make sure that node has
  correct number of wsrep appliers
* galera_bad_wsrep_new_cluster: This test restarts both nodes,
so it is bad on mtr. Make sure it is run alone
* galera_update_limit : Make sure we have PK when needed
galera_as_slave_replay : bf abort was not consistent
* galera_unicode_pk : Add wait_conditions so that all nodes
are part of cluster and DDL and INSERT has replicated before
any further operations are done.
* galera_bf_abort_at_after_statement : Add wait_conditions
to make sure all nodes are part of cluster and that DDL
and INSERT has replicated. Make sure we reset DEBUG_SYNC.

MariaDB server crashes on ARM (weak memory model architecture) while
concurrently executing l_find to load node->key and add_to_purgatory
to store node->key = NULL. l_find then uses key (which is NULL), to
pass it to a comparison function.

The specific problem is the out-of-order execution that happens on a
weak memory model architecture. Two essential reorderings are possible,
which need to be prevented.

a) As l_find has no barriers in place between the optimistic read of
the key field lf_hash.cc#L117 and the verification of link lf_hash.cc#L124,
the processor can reorder the load to happen after the while-loop.

In that case, a concurrent thread executing add_to_purgatory on the same
node can be scheduled to store NULL at the key field lf_alloc-pin.c#L253
before key is loaded in l_find.

b) A node is marked as deleted by a CAS in l_delete lf_hash.cc#L247 and
taken off the list with an upfollowing CAS lf_hash.cc#L252. Only if both
CAS succeed, the key field is written to by add_to_purgatory. However,
due to a missing barrier, the relaxed store of key lf_alloc-pin.c#L253
can be moved ahead of the two CAS operations, which makes the value of
the local purgatory list stored by add_to_purgatory visible to all threads
operating on the list. As the node is not marked as deleted yet, the
same error occurs in l_find.

This change three accesses to be atomic.

* optimistic read of key in l_find lf_hash.cc#L117
* read of link for verification lf_hash.cc#L124
* write of key in add_to_purgatory lf_alloc-pin.c#L253

Reviewers: Sergei Vojtovich, Sergei Golubchik

Fixes: MDEV-23510 / d30c1331a18d875e553f3fcf544997e4f33fb943

  InnoDB fails to restore page0 from doublewrite buffer when the
tablespace is being deferred. In that case, InnoDB doesn't find
INIT_PAGE redo log record for page0 and it leads to failure.
InnoDB should recovery page0 from doublewrite buffer.

Print this piece when we've just made the choice to convert to semi-join.
Also, print it when we've already made that choice before:

  transformation": {
     "select_id": 2,
     "from": "IN (SELECT)",
     "to": "semijoin",
     "chosen": true
   }

Print this piece when we've just made the choice to convert to semi-join.
Also, print it when we've already made that choice before:

  transformation": {
     "select_id": 2,
     "from": "IN (SELECT)",
     "to": "semijoin",
     "chosen": true
   }

Let us create and drop a separate database for getting rid of the
default database in the MDEV-22781 test.

The warning message says the file contains a character which can not be
represented in current codepage (not exactly accurate)

Disable lock elision, due to buggy intrin.h (_xbegin is misspelled)
Fix warnings.

restore the old behavior where without a debugger mtr does not
wait for mysqld to start. It was broken in feacc0aa

MDEV-27036: repeated "table" key resolve for print_explain_json

MDEV-27036: duplicated keys in best_access_path

MDEV-27036: Explain_aggr_filesort::print_json_members: resolve duplicated "filesort" member in Json object

MDEV-27036: Explain_basic_join::
            print_explain_json_interns fixed start_dups_weedout case for main.explain_json test