FAILING ASSERTION: FLEN == LEN
Problem:
Broken invariant triggered when building a unique index on a
binary column and the input data contains duplicate keys. This was broken
in debug builds only.
Fix:
Fixed length of the binary datatype can be greater than length of
the shorter prefix on which index is being created.
AUTO_INCREMENT_INCREMENT
Problem:
=======
When auto_increment_increment system variable decreases,
immediate next value of auto increment column is not affected.
Solution:
========
Get the previous inserted value of auto increment column by
subtracting the previous auto_increment_increment from next
auto increment value. After that calculate the current autoinc value
using newly changed auto_increment_increment variable.
Approved by Sunny [rb#4394]
The maximum value for innodb_thread_sleep_delay is 4294967295 (32-bit) or
18446744073709551615 (64-bit) microseconds. This is way too big, since
the max value of innodb_thread_sleep_delay is limited by
innodb_adaptive_max_sleep_delay if that value is set to non-zero value
(its default is 150,000).
Solution
The maximum value of innodb_thread_sleep_delay should be the same as
the maximum value of innodb_adaptive_max_sleep_delay, which is 1000000.
Approved by Jimmy, rb#4429
IN DOCUMENTATION
Problem
-------
The documentation says that we support 'K' prefix
while specifiying size for innodb datafile in the
server variable for innodb_data_file_path ,but the
function srv_parse_megabytes() only handles only
'M' (megabytes) and 'G' (gigabytes) .
Fix
---
Modify srv_parse_megabytes() to handle Kilobytes.
Add in documentation that while specifying size
in KB it should be mentioned in multiples of 1024
other wise they will be rounded off to nearest
MB (megabyte) boundry .(eg if size mentioned
as 2313KB will be considered as 2 MB ).
[ Approved by Marko #rb 2387 ]
ERRORS IN THE FK SECTION
ANALYSIS
--------
Any error during the renaming of the table was
incorrectly logged in the dict_foreign_err_file
and it showed up in foreign key section when
we give the query "show engine innodb status".
FIX
---
Prevent renaming error from being logged in
dict_foreign_err_file section.
[Aprooved by marko #rb 2501 ]
--Implemented CHECK TABLE...QUICK.
Introduce CHECK TABLE...QUICK that would skip the btr_validate_index()
and btr_search_validate() call, and count the no. of records in each index.
Approved by Marko and Kevin. (rb#3567).
AND 'KILL SESSION' LEAD TO CRASH
Analysis:
--------
This situation occurs when the connection executes query
"show engine innodb status" and this connection is killed by
executing statement "kill <con>" by another connection.
In function "innodb_show_status", function "stat_print"
is called to print the status but return value of function
is not checked. After killing connection, if write to
connection fails then error is returned and same is set
in Diagnostic area. Since FALSE is returned from
"innodb_show_status" now, assert to check no error
is set in function "set_eof_status" (called from
my_eof) is failing.
Fix:
----
Changed code to check return value of function "stat_print"
in "innodb_show_status".
ha_innobase::records_in_range() should return HA_POS_ERROR for the table during discarded without requesting pages.
The later other handler method should treat the error correctly.
Approved by Sunny in rb#3433
Problem:
When the user specified foreign key name contains "_ibfk_", InnoDB wrongly
tries to rename it.
Solution:
When a table is renamed, all its associated foreign keys will also be renamed,
only if the foreign key names are automatically generated. If the foreign key
names are given by the user, even if it has _ibfk_ in it, it must not be
renamed.
rb#2935 approved by Jimmy, Krunal and Satya
SERIALIZABLE
Problem:
The documentation claims that WITH CONSISTENT SNAPSHOT will work for both
REPEATABLE READ and SERIALIZABLE isolation levels. But it will work only
for REPEATABLE READ isolation level. Also, the clause WITH CONSISTENT
SNAPSHOT is silently ignored when it is not applicable to the given isolation
level.
Solution:
Generate a warning when the clause WITH CONSISTENT SNAPSHOT is ignored.
rb#2797 approved by Kevin.
Note: Support team wanted to push this to 5.5+.
Analysis
--------
The pthread_mutex commit_threads_m was initiliazed but never
used.
Fix
---
Removing the commit_threads_m mutex from the code base.
[ Approved by Marko rb#2475]
DDL AND I_S QUERIES
Skip partially created indexes (ones whose name starts with TEMP_INDEX_PREFIX)
from stats gathering.
Because InnoDB reports HA_INPLACE_ADD_INDEX_NO_WRITE to MySQL, the latter
allows parallel execution of ha_innobase::add_index() and ha_innobase::info().
Reviewed by: Inaam (rb:2613)
IF IT HAS A WRONG COUNT
If CHECK TABLE finds that a secondary index contains the wrong
number of entries, it used to report an error but not mark the
index as corrupt. The error means that the index should be rebuilt,
which can be done with ALTER TABLE DROP INDEX and ALTER TABLE ADD
INDEX. But just in case the DBA does not pay any attention to the
output of CHECK TABLE, the secondary index should be marked as
corrupted so that it is not used again.
Approved by Inaam in RB:2607
i_s_innodb_buffer_page_get_info(): Do not read the buffer block frame
contents of read-fixed blocks, because it may be invalid or
uninitialized. When we are going to decompress or read a block, we
will put it into buf_pool->page_hash and buf_pool->LRU, read-fix the
block and release the mutexes for the duration of the reading or
decompression.
rb#2500 approved by Jimmy Yang
AFTER A ROW IS READ
Approved by: Sunny Bains rb://2425
Don't release concurrency tickets when asked to release
btr_search_latch. This is a 5.5 only bug. It is already
fixed in 5.6 upwards.
== Analysis ==
Both change buffer pages and on-disk indexes pages are marked as
FIL_PAGE_INDEX. So all ibuf index pages will classify as INDEX with NULL
table_name and index_name.
== Solution ==
A new page type for ibuf data pages named I_S_PAGE_TYPE_IBUF is defined. All
these pages whose index_id equal (DICT_IBUF_ID_MIN + IBUF_SPACE_ID) will
classify as IBUF_DATA instead of INDEX in INNODB_BUFFER_PAGE
and INNODB_BUFFER_PAGE_LRU.
This fix is only for IS reporting, both on-disk and buffer pool structures
keep unchanged.
Approved by both Marko and Jimmy. rb#2334
TRANSACTION ROLLBACK
Problem:
=======
"prepare_commit_mutex" is acquired during "innobase_xa_prepare"
and it is freed only in "innobase_commit". After prepare,
if the commit operation fails the transaction is rolled back
but the mutex is not released.
Analysis:
========
During transaction commit process transaction is prepared and
the "prepare_commit_mutex" is acquired to preserve the order
of commit. After prepare write to binlog is initiated.
File: sql/handler.cc
if (error || (is_real_trans && xid &&
-----> (error= !(cookie= tc_log->log_xid(thd, xid)))))
{
ha_rollback_trans(thd, all);
In the above code "tc_log->log_xid" operation fails.
When the write to binlog fails the transaction is rolled back
with out freeing the mutex. A subsequent "INSERT" operation
tries to acquire the same mutex during its commit process
and the server aborts.
Fix:
===
"prepare_commit_mutex" is freed during "innobase_rollback".
Bug #16754901 PARS_INFO_FREE NOT CALLED IN DICT_CREATE_ADD_FOREIGN_TO_DICTIONARY
Problem:
There are two situations here. The constraint name is explicitly
given by the user and the constraint name is automatically generated
by InnoDB. In the case of generated constraint name, it is formed by
adding table name as prefix. The table names are stored internally in
my_charset_filename. In the case of constraint name explicitly given
by the user, it is stored in UTF8 format itself. So, in some
situations the constraint name is in utf8 and in some situations it is
in my_charset_filename format. Hence this problem.
Solution:
Always store the foreign key constraint name in UTF-8 even when
automatically generated.
Bug #16754901 PARS_INFO_FREE NOT CALLED IN DICT_CREATE_ADD_FOREIGN_TO_DICTIONARY
Problem:
There was a memory leak in the function dict_create_add_foreign_to_dictionary().
The allocated pars_info_t object is not freed in the error code path.
Solution:
Allocate the pars_info_t object after the error checking.
rb#2368 in review
OPENING MISSING PARTITION
In the ha_innobase::open() call, for normal tables, there is no retry logic.
But for partitioned tables, there is a retry logic introduced as fix for:
http://bugs.mysql.com/bug.php?id=33349https://support.mysql.com/view.php?id=21080
The Bug#33349, does not provide sufficient information to analyze the original
problem. The original problem reported by bug#33349 is also minor (just an
annoyance and no loss of functionality). Most importantly, the retry logic
has been introduced without any associated test case.
So we are removing the retry logic for partitioned tables. When the original
problem occurs, a different solution will be explored.
UPDATES
After checking that the table has changed too much in
row_update_statistics_if_needed() and calling dict_update_statistics(),
also check if the same condition holds after acquiring the table stats
latch. This is to avoid multiple threads concurrently entering and
executing the stats update code.
Approved by: Marko (rb:2186)
This is a deadlock that will also be fixed in the server by
Bug #11844915 - HANG IN THDVAR MUTEX ACQUISITION.
So this is a simple alternate method of fixing the same problem,
but from within InnoDB.
The simple change is to make rename table start a transaction
before locking dict_sys->mutex since thd_supports_xa() can call
THDVAR which can lock a mutex, LOCK_global_system_variables, that
is used in the server by many other activities. At least one of
those, sys_var::update(), can call back into InnoDB and try to
lock dict_sys->mutex while holding LOCK_global_system_variables.
The other bug fix for 11844915 eliminates the use of
LOCK_global_system_variables for calls to THDVAR.
Approved by marko in http://rb.no.oracle.com/rb/r/2000/
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.
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)
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.
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.
