There was a race condition in the rollback of TRX_UNDO_UPD_DEL_REC.
Once row_undo_mod_clust() has rolled back the changes by the rolling-back
transaction, it attempts to purge the delete-marked record, if possible, in a
separate mini-transaction.
However, row_undo_mod_remove_clust_low() fails to check if the DB_TRX_ID of
the record that it found after repositioning the cursor, is still the same.
If it is not, it means that the record was purged and another record was
inserted in its place.
So, the rollback would have performed an incorrect purge, breaking the
locking rules and causing corruption.
The problem was found by creating a table that contains a unique
secondary index and a primary key, and two threads running REPLACE
with only one value for the unique column, so that the uniqueness
constraint would be violated all the time, leading to statement
rollback.
This bug exists in all InnoDB versions (I checked MySQL 3.23.53).
It has become easier to repeat in 5.5 and 5.6 thanks to scalability
improvements and a dedicated purge thread.
rb#3085 approved by Jimmy Yang
trx_undo_prev_version_build() should confirm existence of inherited (not-own) external pages.
Bug #14676084 : ROW_UNDO_MOD_UPD_DEL_SEC() DOESN'T NEED UNDO_ROW AND UNDO_EXT INITIALIZED
mtr script could hit the assertion error !bpage->file_page_was_freed using this path.
So, also fixed
rb://1337 approved by Marko Makela.
TRANSACTION ROLLBACK
Description: During the rollback operation, a blob page
is removed earlier than desired. Consider following scenario:
1. create table t1(a int primary key,b blob) engine=innodb;
2. insert into t1 values (1,repeat('b',9000));
3. begin;
4. update t1 set b=concat(b,'b');
5. update t1 set a=a+1;
6. insert into t1 values (1,repeat('b',9000));
7. rollback;
The update operation in line 5 produces 2 undo log record. The first
undo record (TRX_UNDO_DEL_MARK_REC) goes to trx->update_undo and the
second undo record (TRX_UNDO_INSERT_REC) goes to trx->insert_undo.
During rollback, they are executed out of order.
When the undo record TRX_UNDO_DEL_MARK_REC is applied/executed,
the blob ownership is also reset. Because of this the blob page
is released earlier than desired. This blob page must have been
freed only as part of applying/executing the undo record
TRX_UNDO_INSERT_REC.
This problem can be avoided by executing the undo records in
order. This patch will make innodb to execute the undo records
in order.
rb://1125 approved by Marko.
This fix does not remove the underlying cause of the assertion
failure. It just works around the problem, allowing a corrupted
secondary index to be fixed by DROP INDEX and CREATE INDEX (or in the
worst case, by re-creating the table).
ibuf_delete(): If the record to be purged is the last one in the page
or it is not delete-marked, refuse to purge it. Instead, write an
error message to the error log and let a debug assertion fail.
ibuf_set_del_mark(): If the record to be delete-marked is not found,
display some more information in the error log and let a debug
assertion fail.
row_undo_mod_del_unmark_sec_and_undo_update(),
row_upd_sec_index_entry(): Let a debug assertion fail when the record
to be delete-marked is not found.
buf_page_print(): Add ut_ad(0) so that corruption will be more
prominent in stress testing with debug binaries. Add ut_ad(0) here and
there where corruption is noticed.
btr_corruption_report(): Display some data on page_is_comp() mismatch.
btr_assert_not_corrupted(): A wrapper around btr_corruption_report().
Assert that page_is_comp() agrees with the table flags.
rb:911 approved by Inaam Rana
Bug#12612184 RACE CONDITION AFTER BTR_CUR_PESSIMISTIC_UPDATE()
The fix introduced potentially more severe crash recovery problems
than the bug causes. Revert the fix for now.
Also addressed issues in bug #11745133, where we could mark a table
corrupted instead of crashing the server when found a corrupted buffer/page
if the table created with innodb_file_per_table on.
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
Fix compiler warning:
row/row0umod.c: In function 'row_undo_mod_clust_low':
row/row0umod.c:92:9: error: variable 'success' set but not used [-Werror=unused-but-set-variable]
------------------------------------------------------------
revno: 3488
revision-id: marko.makela@oracle.com-20100601103738-upm8awahesmeh9dr
parent: vasil.dimov@oracle.com-20100531163540-9fu3prbn2asqwdi5
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Tue 2010-06-01 13:37:38 +0300
message:
Bug#53812: assert row/row0umod.c line 660 in txn rollback after crash recovery
row_undo_mod_upd_exist_sec(): Tolerate a failure to build the index entry
for a DYNAMIC or COMPRESSED table during crash recovery.
bzr branch mysql-5.1-performance-version mysql-trunk # Summit
cd mysql-trunk
bzr merge mysql-5.1-innodb_plugin # which is 5.1 + Innodb plugin
bzr rm innobase # remove the builtin
Next step: build, test fixes.
Bugs fixed:
- Bug #20877: InnoDB data dictionary memory footprint is too big
- Bug #13544: Second delete of same row in transaction illustrates non-optimal locking
- Bug #20791: valgrind errors in InnoDB
Bugs fixed:
- Bug #20791 valgrind errors in InnoDB
Remove Valgrind warning of Bug #20791 : in new database
creation, we read the doublewrite buffer magic number from
uninitialized memory; the code worked because it was extremely
unlikely that the memory would contain the magic number
- Bug #21784 DROP TABLE crashes 5.1.12-pre if concurrent
queries on the table
remove update_thd() in ::store_lock()
Also includes numerous coding style fixes, etc. See file-level
comments for details.
Fixed BUGS:
#3300: "UPDATE statement with no index column in where condition locks
all rows"
Implement semi-consistent read to reduce lock conflicts at the cost
of breaking serializability.
ha_innobase::unlock_row(): reset the "did semi consistent read" flag
ha_innobase::was_semi_consistent_read(),
ha_innobase::try_semi_consistent_read(): new methods
row_prebuilt_t, row_create_prebuilt(): add field row_read_type for
keeping track of semi-consistent reads
row_vers_build_for_semi_consistent_read(),
row_sel_build_committed_vers_for_mysql(): new functions
row_search_for_mysql(): implement semi-consistent reads
#9802: "Foreign key checks disallow alter table".
Added test cases.
#12456: "Cursor shows incorrect data - DML does not affect,
probably caching"
This patch implements a high-granularity read view to be used with
cursors. In this high-granularity consistent read view modifications
done by the creating transaction after the cursor is created or
future transactions are not visible. But those modifications that
transaction did before the cursor was created are visible.
#12701: "Support >4GB buffer pool and log files on 64-bit Windows"
Do not call os_file_create_tmpfile() at runtime. Instead, create all
tempfiles at startup and guard access to them with mutexes.
#13778: "If FOREIGN_KEY_CHECKS=0, one can create inconsistent FOREIGN KEYs".
When FOREIGN_KEY_CHECKS=0 we still need to check that datatypes between
foreign key references are compatible.
#14189: "VARBINARY and BINARY variables: trailing space ignored with InnoDB"
innobase_init(): Assert that
DATA_MYSQL_BINARY_CHARSET_COLL == my_charset_bin.number.
dtype_get_pad_char(): Do not pad VARBINARY or BINARY columns.
row_ins_cascade_calc_update_vec(): Refuse ON UPDATE CASCADE when trying
to change the length of a VARBINARY column that refers to or is referenced
by a BINARY column. BINARY columns are no longer padded on comparison,
and thus they cannot be padded on storage either.
#14747: "Race condition can cause btr_search_drop_page_hash_index() to crash"
Note that buf_block_t::index should be protected by btr_search_latch
or an s-latch or x-latch on the index page.
btr_search_drop_page_hash_index(): Read block->index while holding
btr_search_latch and use the cached value in the loop. Remove some
redundant assertions.
#15108: "mysqld crashes when innodb_log_file_size is set > 4G"
#15308: "Problem of Order with Enum Column in Primary Key"
#15550: "mysqld crashes in printing a FOREIGN KEY error in InnoDB"
row_ins_foreign_report_add_err(): When printing the parent record,
use the index in the parent table rather than the index in the child table.
#15653: "Slow inserts to InnoDB if many thousands of .ibd files"
Keep track on unflushed modifications to file spaces. When there are tens
of thousands of file spaces, flushing all files in fil_flush_file_spaces()
would be very slow.
fil_flush_file_spaces(): Only flush unflushed file spaces.
fil_space_t, fil_system_t: Add a list of unflushed spaces.
#15991: "innodb-file-per-table + symlink database + rename = cr"
os_file_handle_error(): Map the error codes EXDEV, ENOTDIR, and EISDIR
to the new code OS_FILE_PATH_ERROR. Treat this code as OS_FILE_PATH_ERROR.
This fixes the crash on RENAME TABLE when the .ibd file is a symbolic link
to a different file system.
#16157: "InnoDB crashes when main location settings are empty"
This patch is from Heikki.
#16298: "InnoDB segfaults in INSERTs in upgrade of 4.0 -> 5.0 tables
with VARCHAR BINARY"
dict_load_columns(): Set the charset-collation code
DATA_MYSQL_BINARY_CHARSET_COLL for those binary string columns
that lack a charset-collation code, i.e., the tables were created
with an older version of MySQL/InnoDB than 4.1.2.
#16229: "MySQL/InnoDB uses full explicit table locks in trigger processing"
Take a InnoDB table lock only if user has explicitly requested a table
lock. Added some additional comments to store_lock() and external_lock().
#16387: "InnoDB crash when dropping a foreign key <table>_ibfk_0"
Do not mistake TABLENAME_ibfk_0 for auto-generated id.
dict_table_get_highest_foreign_id(): Ignore foreign constraint
identifiers starting with the pattern TABLENAME_ibfk_0.
#16582: "InnoDB: Error in an adaptive hash index pointer to page"
Account for a race condition when dropping the adaptive hash index
for a B-tree page.
btr_search_drop_page_hash_index(): Retry the operation if a hash index
with different parameters was built meanwhile. Add diagnostics for the
case that hash node pointers to the page remain.
btr_search_info_update_hash(), btr_search_info_update_slow():
Document the parameter "info" as in/out.
#16814: "SHOW INNODB STATUS format error in LATEST FOREIGN KEY ERROR
section"
Add a missing newline to the LAST FOREIGN KEY ERROR section in SHOW
INNODB STATUS output.
dict_foreign_error_report(): Always print a newline after invoking
dict_print_info_on_foreign_key_in_create_format().
#16827: "Better InnoDB error message if ibdata files omitted from my.cnf"
#17126: "CHECK TABLE on InnoDB causes a short hang during check of adaptive
hash"
CHECK TABLE blocking other queries, by releasing the btr_search_latch
periodically during the adaptive hash table validation.
#17405: "Valgrind: conditional jump or move depends on unititialised values"
buf_block_init(): Reset magic_n, buf_fix_count and io_fix to avoid
testing uninitialized variables.
