It causes lots of failures due to
Bug#54861 Additional connections not handled properly in mtr --embedded
should be re-enabled when that bug is resolved

and clarifies the invariant in dict_table_get_on_id().
  
In Mar 2007 Marko observed a crash during recovery, the crash resulted from
an UNDO operation on a system table. His solution was to acquire an X lock on
the data dictionary, this in hindsight was an overkill. It is unclear what
caused the crash, current hypothesis is that it was a memory corruption.
  
The X lock results in performance issues by when undoing changes due to
rollback during normal operation on regular tables.
  
Why the change is safe:
======================
The InnoDB code has changed since the original X lock change was made. In the
new code we always lock the data dictionary in X mode during startup when
UNDOing operations on the system tables (this is a given). This ensures that
the crash Marko observed cannot happen as long as all transactions that update
the system tables follow the standard rules by setting the appropriate DICT_OP
flag when writing the log records when they make the changes.
  
If transactions violate the above mentioned rule then during recovery (at
startup) the rollback code (see trx0roll.c) will not acquire the X lock
and we will see the crash again.  This will however be a different bug.

------------------------------------------------------------
revno: 3523
revision-id: marko.makela@oracle.com-20100624104620-pklunowaigv7quu9
parent: jimmy.yang@oracle.com-20100624021010-oh2hnp8e1xbaax6u
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Thu 2010-06-24 13:46:20 +0300
message:
  Bug#54679: alter table causes compressed row_format to revert to compact

  ha_innobase::create(): Add the local variable row_type = form->s->row_type.
  Adjust it to ROW_TYPE_COMPRESSED when ROW_FORMAT is not specified or inherited
  but KEY_BLOCK_SIZE is. Observe the inherited ROW_FORMAT even when it is not
  explicitly specified.

  innodb_bug54679.test: New test, to test the bug and to ensure that there are
  no regressions. (The only difference in the test result without the patch
  applied is that the first ALTER TABLE changes ROW_FORMAT to Compact.)

trx_undo_build_roll_ptr(): Clarify the assertion on is_insert being 0 or 1.

TRX_SYS_FILE_FORMAT_TAG: Remove "extra" space after period in the comment.
See also http://desktoppub.about.com/cs/typespacing/a/onetwospaces.htm

about trx_id being possibly uninitialized in trx_undo_parse_page_header().
The warning remains when UNIV_DEBUG or UNIV_MUST_NOT_INLINE is enabled.

```---------------------------------------------------------
revno: 3520
committer: Jimmy Yang <jimmy.yang@oracle.com>
branch nick: mysql-5.1-innodb
timestamp: Tue 2010-06-22 19:04:31 -0700
message:
  Fix bug #54044, Create temporary tables and using innodb crashes. Screen
  out NULL type columns, and return without creating the table.
  
  rb://378 approved by Marko
```

---------------------------------------------------------

This will make PB2 test InnoDB with UNIV_DEBUG on its *_debug platforms

Discussed with:	Marko (on IRC)

  ------------------------------------------------------------
  revno: 3517
  revision-id: vasil.dimov@oracle.com-20100622163043-dc0lxy0byg74viet
  parent: marko.makela@oracle.com-20100621095148-8g73k8k68dpj080u
  committer: Vasil Dimov <vasil.dimov@oracle.com>
  branch nick: mysql-5.1-innodb
  timestamp: Tue 2010-06-22 19:30:43 +0300
  message:
    Fix Bug#47991 InnoDB Dictionary Cache memory usage increases indefinitely
    when renaming tables
    
    Allocate the table name using ut_malloc() instead of table->heap because
    the latter cannot be freed.
    
    Adjust dict_sys->size calculations all over the code.
    
    Change dict_table_t::name from const char* to char* because we need to
    ut_malloc()/ut_free() it.
    
    Reviewed by:	Inaam, Marko, Heikki (rb://384)
    Approved by:	Heikki (rb://384)
  ------------------------------------------------------------

------------------------------------------------------------
revno: 3517
revision-id: marko.makela@oracle.com-20100622115215-kxtzx7xuugcxd375
parent: marko.makela@oracle.com-20100621095148-8g73k8k68dpj080u
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Tue 2010-06-22 14:52:15 +0300
message:
  Bug#54686 "field->col->mtype == type" assertion error at row/row0sel.c
  ha_innobase::index_read(), ha_innobase::records_in_range(): Check that
  the index is useable before invoking row_sel_convert_mysql_key_to_innobase().

  This fix is based on a suggestion by Yasufumi Kinoshita.

Silence GCC warnings about dereferencing a type-punned pointer.
Approved by Jimmy Yang.

Approved by Jimmy Yang.

Make a call to log_free_check() on all DML paths.

Implement WITH_VALGRIND for the CMake build.

------------------------------------------------------------
revno: 3515
revision-id: marko.makela@oracle.com-20100621094008-o9fa153s3f09merw
parent: vasil.dimov@oracle.com-20100618085155-xnm469cbhedqea96
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Mon 2010-06-21 12:40:08 +0300
message:
  Bug #54658: InnoDB: Warning: allocated tablespace %lu, old maximum was 0

  dict_check_tablespaces_and_store_max_id(): Initialize max_space_id
  and fil_system->max_assigned_id from DICT_HDR_MAX_SPACE_ID.

  fil_space_create(): Suppress the warning unless !recv_recovery_on
  (do not complain while applying the redo log).

is going to be 1.1.1.

and innodb_file_format_max two system variables. And this also fixes
bug #53654 after 2nd shutdown innodb_file_format_check attains strange
values.

rb://366 approved by Marko

On [Open]Solaris/x86 the FPU was not switched to 64-bit double
precision mode when the server binary was built with Sun
Studio. That caused GIS test failures due to differences in
expected and actual results.

the 1.1.1 release will be included inside MySQL 5.5.5 and is
up to (inclusive):
vasil.dimov@oracle.com-20100602124314-21l3cb27w4rbfqrq

root cause of 52208 resulted in another test failure
in 5.1.

Reorder code breaks when finding tests skipped due to --skip-rpl etc.
Add simple test that master_opt is non-empty

Kill mysqltest and call mtr_kill_leftovers() before terminating

Let mtr lookup the plugins, rather than hard-coding autotools lib path.