FROM SHOW CREATE
Problem: The length of the internally generated foreign key name
is not checked.
Solution: The length of the internally generated foreign key name is
checked. If it is greater than the allowed limit, an error message
is reported. Also, the constraint name is printed in the same manner
as the table name, using the system charset information.
rb://1969 approved by Marko.
DEREFERENCING UT_DBG_NULL_PTR
The abort() call is standard C but InnoDB only uses it in GCC
environments. UT_DBG_USE_ABORT is not defined the code crashed
by dereferencing a null pointer instead of calling abort().
Other code throughout MySQL including ndb, sql, mysys and other
places call abort() directly.
This bug also affects innodb.innodb_bug14147491.test which fails
randomly on windows because of this issue.
Approved by marko in http://rb.no.oracle.com/rb/r/1936/
I/O IS ASYNC
rb://1934
approved by: Mikael Ronstrom (over email)
When submitting AIO read request don't signal that the thread is
about to wait on DISKIO
WITH --SKIP-INNODB
Description
-----------
If the server is started with skip-innodb or InnoDB otherwise fails to
start, any one of these queries will crash the server:
For (5.5)
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_PAGE;
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_PAGE_LRU;
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_POOL_STATS;
In (5.6+) ,following queries will also crash the server.
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_INDEXES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_COLUMNS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FIELDS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_DATAFILES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES;
FIX
----
When Innodb is not active we must prevent it from processing
these tables,so we return a warning saying that innodb is not
active.
Approved by marko (http://rb.no.oracle.com/rb/r/1891)
With innodb_change_buffering enabled, Innodb buffers
all modifications to secondary index leaf pages when
the leaf pages are not in buffer pool.
Crash InnoDB while an IBUF_OP_DELETE is being applied.
Restart and note that the same record can be applied
again which may lead to crash.
Mark the change buffer record processed, so that it will
not be merged again in case the server crashes between
the following mtr_commit() and the subsequent mtr_commit()
of deleting the change buffer record.
Testcase: No testcase because it is difficult to get the
timing right with the two asyncronous task purge and change
buffering
Approved by Marko. rb#1893
Get rid of O(n^2) scan in dyn array (mtr->memo) operations, accessing
the dyn array blocks directly.
dyn_array_get_last_block(), dyn_array_get_next_block(),
dyn_array_get_prev_block(): Define as a constness-preserving macro.
Add const qualifiers to many dyn_array functions.
mtr_memo_slot_release_func(): Renamed from mtr_memo_slot_release():
Make mtr_t* a debug-only parameter. Assume that slot->object != NULL.
mtr_memo_pop_all(): Access the dyn_array blocks directly, replacing
O(n^2) operation with O(n).
mtr_memo_release(): Access the dyn_array blocks directly, replacing
O(n^2) operation with O(n). This caused the performance problem.
rb#1540 approved by Jimmy Yang
WITH AN ASSERTION
Recently we added check to handle kill query signal for long operating
queries.
While the query interruption is reported it must to ensure cursor is restore
to proper state for HANDLER interface to work correctly.
Normal select query will not face this problem, as on recieving interrupt,
select query is aborted and new select query result in re-initialization
(including cursor).
rb://1836. Approved by Marko.
Problem:
During the index intersect access method, the SQL layer will access one row,
that satisfies a set of conditions, using an index i1. And then it will try to
access the same row, with other set of conditions using the next index i2. If
the fetch from i2 fails (we are talking about an error situation here and not
simply an unmatched row situation), then it will unlock the row accessed via
i1. This will work in all situations except deadlock error.
When a deadlock happens, InnoDB will rollback the transaction. InnoDB intimates
the SQL layer about this through the THD::transaction_rollback_request member.
But this is not currently used by the SQL layer.
Solution:
When an error happens, the SQL layer must check the
THD::transaction_rollback_request member, before calling handler::unlock_row().
We have also added a debug assert in ha_innobase::unlock_row() checking that
it must be called only when the transaction is in active state.
rb#1773 approved by Marko and Sunny.
HANG
Problem Statement:
When the operation RENAME TABLE is about rename the tablespace of the
table, it will stop all i/o operations on the tablespace temporarily.
For this the fil_space_t::stop_ios member is used.
Once the fil_space_t::stop_ios member is set to TRUE in the RENAME
TABLE operation, it is expected that no new i/o operation will be done
on the tablespace and all pending i/o operation can be completed on
the tablespace.
If the pending i/o operations initiate any new i/o operations then
there will be deadlock. The RENAME TABLE operation will be waiting
for pending i/o on the tablespace to be completed, and the pending i/o
operations will be waiting on the RENAME TABLE operation to set the
file_space_t::stop_ios flag to be set to FALSE.
But in the given scenario the pending i/o operations did not initiate
new i/o. But they where still unnecessarily checking the
fil_space_t::stop_ios flag. This resulted in deadlock.
Solution:
I noticed that this deadlock happens in fil_space_get_size() and
fil_space_get_zip_size() in the i/o threads. These functions check
the stop_ios flag even when no i/o will be initiated. I modified
these functions to ensure that they check the stop_ios flag only when
they will be initiating an i/o operation. This solves the problem.
rb://1635 (mysql-5.5)
rb://1660 (mysql-trunk) approved by Inaam, Jimmy, and ima.
DTUPLE_CREATE_FROM_MEM()
Align to word-size the memory occupied by tuple_buf[] memory chunk.
I confirm that this change fixes the SIGBUS on Solaris.
Approved by: Marko (via IM)
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.
btr_lift_page_up() writes wrong page number (different by -1) for upper than father page.
But in almost all of the cases, the father page should be root page, no upper
pages. It is very rare path.
In addition the leaf page should not be lifted unless the father page is root.
Because the branch pages should not become the leaf pages.
rb://1336 approved by Marko Makela.
btr_lift_page_up() writes wrong page number (different by -1) for upper than father page.
But in almost all of the cases, the father page should be root page, no upper
pages. It is very rare path.
In addition the leaf page should not be lifted unless the father page is root.
Because the branch pages should not become the leaf pages.
rb://1336 approved by Marko Makela.
LEN <= SIZEOF(ULONGLONG)
This bug was caught in the WL#6255 ALTER TABLE...ADD COLUMN in MySQL
5.6, but there is a bug in all InnoDB versions that support
auto-increment columns.
row_search_autoinc_read_column(): When reading the maximum value of
the auto-increment column, and the column only contains NULL values,
return 0. This corresponds to the case when the table is empty in
row_search_max_autoinc().
rb:1415 approved by Sunny Bains
SECONDARY INDEX UPDATES MAKE CONSISTENT READS DO O(N^2) UNDO PAGE
LOOKUPS (honoring kill query while accessing sec_index)
If secondary index is being used for select query evaluation and this
query is operating with consistent read snapshot it might take good time for
secondary index to return back control to mysql as MVCC would kick in.
If user issues "kill query <id>" while query is actively accessing
secondary index it will not be honored as there is no hook to check
for this condition. Added hook for this check.
-----
Parallely secondary index taking too long to evaluate for consistent
read snapshot case is being examined for performance improvement. WL#6540.
SECONDARY INDEX UPDATES MAKE CONSISTENT READS DO O(N^2) UNDO PAGE
LOOKUPS (honoring kill query while accessing sec_index)
If secondary index is being used for select query evaluation and this
query is operating with consistent read snapshot it might take good time for
secondary index to return back control to mysql as MVCC would kick in.
If user issues "kill query <id>" while query is actively accessing
secondary index it will not be honored as there is no hook to check
for this condition. Added hook for this check.
-----
Parallely secondary index taking too long to evaluate for consistent
read snapshot case is being examined for performance improvement. WL#6540.
