row_build_index_entry(): In innodb_file_format=Barracuda
(ROW_FORMAT=DYNAMIC or ROW_FORMAT=COMPRESSED), a secondary index on a
full column can refer to a field that is stored off-page in the
clustered index record. Take that into account.

rb:692 approved by Jimmy Yang

Before this fix, the test performance_schema.relaylog would fail
with sporadic failures related to statistics on update_cond.

The reason for these failures is that thread scheduling makes
impossible to predict if instrumented conditions will be used on not.

The fix is to relax the test case, to not collect statistics about:
- wait/synch/cond/sql/MYSQL_BIN_LOG::update_cond
- wait/synch/cond/sql/MYSQL_RELAY_LOG::update_cond

around the declaration of trx_assert_recovered().

Update copyright comment in innochecksum.

Before this fix, a server executing 1009 queries in 1000 seconds would give a status of:
Queries per second avg: 1.9
The printf format used to print the decimal part, computed separately, is incorrect.

With this fix, the correct result is printed:
Queries per second avg: 1.009

Tested manually, no test case provided.

Refactor the !rec_offs_any_extern relaxation in row_build().

trx_assert_active(trx_id): Assert that the given transaction is active.
(In the 5.1 built-in InnoDB, there is no trx->is_recovered field.)

trx_assert_recovered(trx_id): Assert that the given transaction is
active and has been recovered after a crash.

row_build(): Replace a bunch of code with an assertion that invokes
trx_assert_active() or trx_assert_recovered() and row_get_rec_trx_id().

row_get_trx_id_offset(): Make the function inlined. Remove the unused
parameter rec, and make all parameters const.

row_get_rec_trx_id(), row_get_rec_roll_ptr(): Make all parameters const.

rb:691 approved by Jimmy Yang

DB_COL_APPEARS_TWICE_IN_INDEX: Remove. This condition is already
checked and reported by MySQL before passing the index definition to
the storage engine.

row_create_index_for_mysql(): Remove the redundant check for
DB_COL_APPEARS_TWICE_IN_INDEX. When enforcing the column prefix index
limit, invoke dict_mem_index_free(index) to plug the memory leak. In
the loop, use index->n_def instead of dict_index_get_n_fields(index),
because the latter would be 0 for indexes that have not been copied to
the data dictionary cache.

innodb-use-sys-malloc.test:

Add test cases for attempting to trigger the error checks in
row_create_index_for_mysql(). Before MySQL 5.5 and WL#5743, the leak
is only reproducible if ha_innobase::max_supported_key_part_length()
returned a higher limit than the one used in
row_create_index_for_mysql().

In MySQL 5.5 and later, the leak is reproducible with
innodb_large_prefix=true.

rb:688 approved by Jimmy Yang

page_zip_dir_elems(): New function, refactored from page_zip_dir_size().

page_zip_dir_size(): Use page_zip_dir_elems()

page_zip_dir_start_offs(): New function: Gets an offset to the
compressed page trailer (the dense page directory), including deleted
records (the free list)

page_zip_dir_start_low(page_zip, n_dense): Constness-preserving
wrapper macro for page_zip_dir_start_offs().

page_zip_dir_start(page_zip): Constness-preserving
wrapper macro for page_zip_dir_start_offs().

page_zip_decompress_node_ptrs(), page_zip_decompress_clust(): Replace
a formula with a fully equivalent page_zip_dir_start_low() call.

page_zip_write_rec(), page_zip_parse_write_node_ptr(),
page_zip_write_node_ptr(), page_zip_write_trx_id_and_roll_ptr(),
page_zip_clear_rec(): Replace a formula with an almost equivalent
page_zip_dir_start() call.
It is OK to replace page_dir_get_n_heap(page) with
page_dir_get_n_heap(page_zip->data), because
ut_ad(page_zip_header_cmp(page_zip, page)) or
page_zip_validate(page_zip, page) asserts that the
page headers are identical.

rb:687 approved by Jimmy Yang

BOGUS "THE TABLE MYSQL.PROC IS MISSING,..."

There was a race condition between loading a stored routine
(function/procedure/trigger) specified by fully qualified name
SCHEMA_NAME.PROC_NAME and dropping the stored routine database.

The problem was that there is a window for race condition when one server
thread tries to load a stored routine being executed and the other thread
tries to drop the stored routine schema.

This condition race window exists in implementation of function
mysql_change_db() called by db_load_routine() during loading of stored
routine to cache. Function mysql_change_db() calls check_db_dir_existence()
that might failed because specified database was dropped during concurrent
execution of DROP SCHEMA statement. db_load_routine() calls mysql_change_db()
with flag 'force_switch' set to 'true' value so when referenced db is not found
then my_error() is not called and function mysql_change_db() returns ok.
This shadows information about schema opening error in db_load_routine().
Then db_load_routine() makes attempt to parse stored routine that is failed.
This makes to return error to sp_cache_routines_and_add_tables_aux() but since
during error generation a call to my_error wasn't made and hence
THD::main_da wasn't set we set the generic "mysql.proc table corrupt" error
when running sp_cache_routines_and_add_tables_aux().

The fix is to install an error handler inside db_load_routine() for
the mysql_op_change_db() call, and check later if the ER_BAD_DB_ERROR
was caught.


sql/sql_db.cc:
  Added synchronization point "before_db_dir_check" to emulate a race condition during
  processing of CALL/DROP SCHEMA.

This patch was already pushed to mysql-5.5 by Inaam Rana.

Fix a failure of the re-enabled innodb-index.test in the embedded server.
Apparently, the embedded server does not default to ENGINE=InnoDB when
copying an InnoDB table by CREATE TABLE t2 SELECT * FROM t1;

approved by: Marko
rb://681

Coalescing of free buf_page_t descriptors can prove to be one severe
bottleneck in performance of compression. One such workload where it
hurts badly is DROP TABLE. This patch removes buf_page_t allocations
from buf_buddy and uses ut_malloc instead.
In order to further reduce overhead of colaescing we no longer attempt
to coalesce a block if the corresponding free_list is less than 16 in
size.

This patch fixes a typo in a YaSSL error message.

TO POSITION FIRST CAN CAUSE DATA TO BE CORRUPTED".
 
ALTER TABLE MODIFY/CHANGE ... FIRST did nothing except renaming
columns if new version of the table had exactly the same 
structure as the old one (i.e. as result of such statement, names 
of columns changed their order as specified but data in columns 
didn't). The same thing happened for ALTER TABLE DROP COLUMN/ADD 
COLUMN statements which were supposed to produce new version of
table with exactly the same structure as the old version of table.
I.e. in the latter case the result was the same as if old column 
was renamed instead of being dropped and new column with default
as value being created.
 
Both these problems were caused by the fact that ALTER TABLE
implementation incorrectly interpreted both these situations as 
simple renaming of columns and assumed that in-place ALTER TABLE
algorithm could have been used for them.
 
This patch fixes this problem by ensuring that in cases when some
column is moved to the first position or some column is dropped
the default ALTER TABLE algorithm involving table copying is 
always used. This is achieved by detecting such situations in
mysql_prepare_alter_table() and setting Alter_info::change_level
to ALTER_TABLE_DATA_CHANGED for them.

mysql-test/r/alter_table.result:
  Added test for bug #12652385 - "61493: REORDERING COLUMNS TO
  POSITION FIRST CAN CAUSE DATA TO BE CORRUPTED".
mysql-test/t/alter_table.test:
  Added test for bug #12652385 - "61493: REORDERING COLUMNS TO
  POSITION FIRST CAN CAUSE DATA TO BE CORRUPTED".
sql/sql_table.cc:
  Changed mysql_prepare_alter_table() to detect situations in 
  which we some column moved to the first position or some column 
  is dropped and ensure that such ALTER TABLE statements won't
  be carried out using in-place algorithm. The latter could have 
  happened before this patch if new version of table had the same 
  structure as the old one (except the column names).

marko.makela@oracle.com-20110616072721-8bo92ctixq6eqavr

The buf_pool->zip_clean list is only needed for debugging, or for
recomputing buf_pool->page_hash when resizing the buffer pool. Buffer
pool resizing was never fully implemented. Remove the resizing code,
and define buf_pool->zip_clean only in debug builds.

buf_pool->zip_clean, buf_LRU_insert_zip_clean(): Enclose in
#if defined UNIV_DEBUG || UNIV_BUF_DEBUG.

buf_chunk_free(), buf_chunk_all_free(), buf_pool_shrink(),
buf_pool_page_hash_rebuild(), buf_pool_resize(): Remove (unreachable code).

rb:671 approved by Inaam Rana

There is an apparent problem with page_zip_clear_rec().
In btr_cur_optimistic_update() we do this:

	page_cur_delete_rec(page_cursor, index, offsets, mtr);
...
	rec = btr_cur_insert_if_possible(cursor, new_entry, 0/*n_ext*/, mtr);
	ut_a(rec); /* <- We calculated above the insert would fit */

The problem is that page_cur_delete_rec() could fill the modification
log while doing page_zip_clear_rec(), requiring recompression for the
btr_cur_insert_if_possible(). In a pathological case, the data could
fail to recompress.

page_zip_clear_rec(): Leave the page modification log alone. Only
clear the necessary fields.

rb:673 approved by Jimmy Yang

Replace UNIV_BLOB_NULL_DEBUG with UNIV_DEBUG||UNIV_BLOB_LIGHT_DEBUG. 
Fix known bogus failures.

btr_cur_optimistic_update(): If rec_offs_any_null_extern(), assert that
the current transaction is an incomplete transaction that is being
rolled back in crash recovery.

row_build(): If rec_offs_any_null_extern(), assert that the transaction
that last updated the record was recovered during crash recovery
(and will soon be rolled back).

btr_cur_compress_if_useful(), btr_compress(): Add the parameter ibool
adjust. If adjust=TRUE, adjust the cursor position after compressing
the page.

btr_lift_page_up(): Return a pointer to the father page.

BTR_KEEP_POS_FLAG: A new flag for btr_cur_pessimistic_update().

btr_cur_pessimistic_update(): If *big_rec != NULL and flags &
BTR_KEEP_POS_FLAG, keep the cursor positioned on the updated record.
Also, do not release the index tree x-lock if *big_rec != NULL.

btr_cur_mtr_commit_and_start(): Commits and restarts a
mini-transaction so that it will retain an x-lock on index->lock and
the page of the cursor. This is invoked when
btr_cur_pessimistic_update() returns *big_rec != NULL.

In all callers of btr_cur_pessimistic_update() that do not pass
BTR_KEEP_POS_FLAG, assert that *big_rec == NULL.

btr_cur_compress(): Unused function [in the built-in MySQL 5.1], remove.

page_rec_get_nth(): Return the nth record on the page (an inverse
function of page_rec_get_n_recs_before()). Refactored from
page_get_middle_rec().

page_get_middle_rec(): Invoke page_rec_get_nth().

page_cur_insert_rec_zip_reorg(): Make use of the page directory
shortcuts in page_rec_get_nth() instead of scanning the whole list of
records.

row_ins_clust_index_entry_by_modify(): Pass BTR_KEEP_POS_FLAG to
btr_cur_pessimistic_update().

row_ins_index_entry_low(): If row_ins_clust_index_entry_by_modify()
returns a big_rec, invoke btr_cur_mtr_commit_and_start() in order to
commit and start the mini-transaction without releasing the x-locks on
index->lock and the cursor page, and write the big_rec. Releasing the
page latch in mtr_commit() caused a race condition.

row_upd_clust_rec(): Pass BTR_KEEP_POS_FLAG to
btr_cur_pessimistic_update(). If it returns a big_rec, invoke
btr_cur_mtr_commit_and_start() in order to commit and start the
mini-transaction without releasing the x-locks on index->lock and the
cursor page, and write the big_rec. Releasing the page latch in
mtr_commit() caused a race condition.

sync_thread_add_level(): Add the parameter ibool relock. When TRUE,
bypass the latching order rules.

rw_lock_add_debug_info(): For nested X-lock requests, pass relock=TRUE
to sync_thread_add_level().

rb:678 approved by Jimmy Yang

Some ut_a(!rec_offs_any_null_extern()) assertion failures are indicating
genuine BLOB bugs, others are bogus failures when rolling back incomplete
transactions at crash recovery. This needs more work, and until I get a
chance to work on it, other testing must not be disrupted by this.

revno 2995.37.209
revision id marko.makela@oracle.com-20110518120508-qhn7vz814vn77v5k
parent marko.makela@oracle.com-20110517121555-lmple24qzxqkzep4
timestamp: Wed 2011-05-18 15:05:08 +0300
message:
  Fix a bogus UNIV_SYNC_DEBUG failure in the fix of Bug #59641
  or Oracle Bug #11766513.

  trx_undo_free_prepared(): Do not acquire or release trx->rseg->mutex.
  This code is invoked in the single-threaded part of shutdown, therefore
  a mutex is not needed.