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.
The problem is in the error handling in row_create_table_for_mysql().
In the 'disk full' case we may forget to call dict_mem_table_free() on
the table object.
Approved by: Marko (rb:1377 and rb:1386)
CONSISTENT SNAPSHOT OPTION
A transaction is started with a consistent snapshot. After
the transaction is started new indexes are added to the
table. Now when we issue an update statement, the optimizer
chooses an index. When the index scan is being initialized
via ha_innobase::change_active_index(), InnoDB reports
the error code HA_ERR_TABLE_DEF_CHANGED, with message
stating that "insufficient history for index".
This error message is propagated up to the SQL layer. But
the my_error() api is never called. The statement level
diagnostics area is not updated with the correct error
status (it remains in Diagnostics_area::DA_EMPTY).
Hence the following check in the Protocol::end_statement()
fails.
516 case Diagnostics_area::DA_EMPTY:
517 default:
518 DBUG_ASSERT(0);
519 error= send_ok(thd->server_status, 0, 0, 0, NULL);
520 break;
The fix is to backport the fix of bugs 14365043, 11761652
and 11746399.
14365043 PROTOCOL::END_STATEMENT(): ASSERTION `0' FAILED
11761652 HA_RND_INIT() RESULT CODE NOT CHECKED
11746399 RETURN VALUES OF HA_INDEX_INIT() AND INDEX_INIT() IGNORED
rb://1227 approved by guilhem and mattiasj.
We did not allocate enough bits for index->trx_id_offset, causing an
UPDATE or DELETE of a table with a PRIMARY KEY longer than 1024 bytes
to corrupt the PRIMARY KEY.
dict_index_t: Allocate enough bits.
dict_index_build_internal_clust(): Check for overflow of
index->trx_id_offset. Trip a debug assertion when overflow occurs.
rb:1380 approved by Jimmy Yang
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.
Delete-mark change buffer records when resorting to a pessimistic
delete from the change buffer B-tree. Skip delete-marked records in
the change buffer merge and when estimating whether an operation can
be buffered. Without this fix, we could try to apply the same buffered
changes multiple times if the server was killed at the right moment.
In MySQL 5.5 and later: ibuf_get_volume_buffered_count_func(): Ignore
delete-marked (already processed) records.
ibuf_delete_rec(): Add a crash point before optimistic delete. If the
optimistic delete fails, flag the record processed before
mtr_commit().
ibuf_merge_or_delete_for_page(): Ignore delete-marked (already
processed) records.
Backport to 5.1: Rename btr_cur_del_unmark_for_ibuf() to
btr_cur_set_deleted_flag_for_ibuf() and add a parameter.
rb:1307 approved by Jimmy Yang
page_zip_validate(), page_zip_validate_low(): Add a parameter for the
B-tree index.
page_zip_validate_low(): If the page contents does not match, check
that the record link chains match. Furthermore, if dict_index_t is
passed, check that the records match. (This reduces coverage a bit: if
index=NULL, we will ignore differences in record contents, that is,
the page payload.)
rb:1264 approved by Inaam Rana
rb://1293
approved by: Marko Makela
There is race when dropping a single table tablespace where a reader
thread can initiate a read request before the delete flag is set and
before it is finished the deleting thread can attempt to free the
fil_node.
This patch checks the status in fil_io() to make sure that the
tablespace is not being deleted. If it is being deleted then
an error is returned instead of attempting IO.
THOUGH IT IS NOT.
The following error message is misleading because it claims
that the BLOB space is not counted.
"ERROR 1118 (42000): Row size too large. The maximum row size for
the used table type, not counting BLOBs, is 8126. You have to
change some columns to TEXT or BLOBs"
When the ROW_FORMAT=compact or ROW_FORMAT=REDUNDANT is used,
the BLOB prefix is stored inline along with the row. So
the above error message is changed as follows depending on
the row format used:
For ROW_FORMAT=COMPRESSED or ROW_FORMAT=DYNAMIC, the error
message is as follows:
"ERROR 42000: Row size too large (> 8126). Changing some
columns to TEXT or BLOB may help. In current row format,
BLOB prefix of 0 bytes is stored inline."
For ROW_FORMAT=COMPACT or ROW_FORMAT=REDUNDANT, the error
message is as follows:
"ERROR 42000: Row size too large (> 8126). Changing some
columns to TEXT or BLOB or using ROW_FORMAT=DYNAMIC or
ROW_FORMAT=COMPRESSED may help. In current row
format, BLOB prefix of 768 bytes is stored inline."
rb://1252 approved by Marko Makela
PAGE SPLIT
page_rec_get_nth_const(): Map nth==0 to the page infimum.
btr_compress(adjust=TRUE): Add a debug assertion for nth>0. The cursor
should never be positioned on the page infimum.
btr_index_page_validate(): Add test instrumentation for checking the
return values of page_rec_get_nth_const() during CHECK TABLE, and for
checking that the page directory slot 0 always contains only one
record, the predefined page infimum record.
page_cur_delete_rec(), page_delete_rec_list_end(): Add debug
assertions guarding against accessing the page slot 0.
page_copy_rec_list_start(): Clarify a comment about ret_pos==0.
rb:1248 approved by Jimmy Yang
ha_innodb::records_in_range(): Remove a debug assertion
that prohibits an open range (full table).
The patch by Jorgen Loland only removed the assertion from the
built-in InnoDB, not from the InnoDB Plugin.
ha_innobase::records_in_range(): Remove a debug assertion
that prohibits an open range (full table).
This assertion catches unnecessary calls to this method,
but such calls are not harming correctness.
The ha_innobase table handler contained two search key buffers
(srch_key_val1, srch_key_val2) of fixed size used to store the search
key. The size of these buffers where fixed at
REC_VERSION_56_MAX_INDEX_COL_LEN + 2. But this size is not sufficient
to hold the search key. Hence the following assert in
row_sel_convert_mysql_key_to_innobase() failed.
2438 /* Storing may use at most data_len bytes of buf */
2439
2440 if (UNIV_LIKELY(!is_null)) {
2441 ut_a(buf + data_len <= original_buf + buf_len);
2442 row_mysql_store_col_in_innobase_format(
2443 dfield, buf,
2444 FALSE, /* MySQL key value format col */
2445 key_ptr + data_offset, data_len,
2446 dict_table_is_comp(index->table));
2447 buf += data_len;
2448 }
The buffer size is now calculated with the formula
MAX_KEY_LENGTH + MAX_REF_PARTS*2. This properly takes into account
the extra bytes needed to store the length for each column. An index
can contain a maximum of MAX_REF_PARTS columns in it, and for each
column 2 bytes are needed to store length.
rb://1238 approved by Marko and Vasil Dimov.
Backport from mysql-5.6 the fix
(revision-id sunny.bains@oracle.com-20120315045831-20rgfa4cozxmz7kz)
Bug#13839886 - CRASH IN INNOBASE_NEXT_AUTOINC
The assertion introduce in the fix for Bug#13817703
is too strong, a negative number can be greater
than the column max value, when the column value is
a negative number.
rb://978 Approved by Jimmy Yang.
rb:1236 approved by Marko Makela
WARNING
This patch is for mysql-5.5 only,
to be null-merged to mysql-5.6 and mysql-trunk.
This is a partial rollback of the file io instrumentation,
removing the instrumentation for mysql_file_stat in the archive engine.
See the bug comments for details.
HEURISTICS FOR COMPRESSED PAGE SIZE
The fix of Bug#12845774 was supposed to skip known-to-fail
btr_cur_optimistic_insert() calls. There was only one such call, in
btr_cur_pessimistic_update(). All other callers of
btr_cur_pessimistic_insert() would release and reacquire the B-tree
page latch before attempting the pessimistic insert. This would allow
other threads to restructure the B-tree, allowing (and requiring) the
insert to succeed as an optimistic (single-page) operation.
Failure to attempt an optimistic insert before a pessimistic one would
trigger an attempt to split an empty page.
rb:1234 approved by Sunny Bains
Facebook got a case where the page compresses really well so that
btr_cur_optimistic_update() returns DB_UNDERFLOW, but when a record
gets updated, the compression rate radically changes so that
btr_cur_insert_if_possible() can not insert in place despite
reorganizing/recompressing the page, leading to the assertion failing.
rb:1220 approved by Sunny Bains
COMPRESSED PAGE SIZE
This was submitted as MySQL Bug 61456 and a patch provided by
Facebook. This patch follows the same idea, but instead of adding a
parameter to btr_cur_pessimistic_insert(), we simply remove the
btr_cur_optimistic_insert() call there and add it to the only caller
that needs it.
btr_cur_pessimistic_insert(): Do not try btr_cur_optimistic_insert().
btr_insert_on_non_leaf_level_func(): Invoke btr_cur_optimistic_insert()
before invoking btr_cur_pessimistic_insert().
btr_cur_pessimistic_update(): Clarify in a comment why it is not
necessary to invoke btr_cur_optimistic_insert().
btr_root_raise_and_insert(): Assert that the root page is not empty.
This could happen if a pessimistic insert (involving a split or merge)
is performed without first attempting an optimistic (intra-page) insert.
rb:1219 approved by Sunny Bains
btr_cur_optimistic_insert(): Remove a bogus assertion. The insert may
fail after reorganizing the page.
btr_cur_optimistic_update(): Do not attempt to reorganize compressed pages,
because compression may fail after reorganization.
page_copy_rec_list_start(): Use page_rec_get_nth() to restore to the
ret_pos, which may also be the page infimum.
rb:1221
IN QUERIES
This bug was caused by an incorrect fix of
Bug#13807811 BTR_PCUR_RESTORE_POSITION() CAN SKIP A RECORD
There was nothing wrong with btr_pcur_restore_position(), but with the
use of it in the table scan during index creation.
rb:1206 approved by Jimmy Yang
Problem description:
Table 't' created with two colums having compound index on both the
columns under innodb/myisam engine at remote machine. In the local
machine same table is created undet the federated engine.
A select having where clause with along 'AND' operation gives wrong
results on local machine.
Analysis:
The given query at federated engine is wrongly transformed by
federated::create_where_from_key() function and the same was sent to
the remote machine. Hence the local machine is showing wrong results.
Given query "select c1 from t where c1 <= 2 and c2 = 1;"
Query transformed, after ha_federated::create_where_from_key() function is:
SELECT `c1`, `c2` FROM `t` WHERE (`c1` IS NOT NULL ) AND
( (`c1` >= 2) AND (`c2` <= 1) ) and the same sent to real_query().
In the above the '<=' and '=' conditions were transformed to '>=' and
'<=' respectively.
ha_federated::create_where_from_key() function behaving as below:
The key_range is having both the start_key and end_key. The start_key
is used to get "(`c1` IS NOT NULL )" part of the where clause, this
transformation is correct. The end_key is used to get "( (`c1` >= 2)
AND (`c2` <= 1) )", which is wrong, here the given conditions('<=' and '=')
are changed as wrong conditions('>=' and '<=').
The end_key is having {key = 0x39fa6d0 "", length = 10, keypart_map = 3,
flag = HA_READ_AFTER_KEY}
The store_length is having value '5'. Based on store_length and length
values the condition values is applied in HA_READ_AFTER_KEY switch case.
The switch case 'HA_READ_AFTER_KEY' is applicable to only the last part of
the end_key and for previous parts it is going to 'HA_READ_KEY_OR_NEXT' case,
here the '>=' is getting added as a condition instead of '<='.
Fix:
Updated the 'if' condition in 'HA_READ_AFTER_KEY' case to affect for all
parts of the end_key. i.e 'i > 0' will used for end_key, Hence added it in
the if condition.
mysql-test/suite/federated/federated.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_archive.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_13118.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_25714.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_35333.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_debug.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_innodb.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_server.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_transactions.test:
modified the federated.inc file location
mysql-test/suite/federated/include/federated.inc:
moved the file from federated suite to federated/include folder
mysql-test/suite/federated/include/federated_cleanup.inc:
moved the file from federated suite to federated/include folder
mysql-test/suite/federated/include/have_federated_db.inc:
moved the file from federated suite to federated/include folder
storage/federated/ha_federated.cc:
updated the 'if condition' in ha_federated::create_where_from_key()
function.
Backporting the WL#5716, "Information schema table for InnoDB
buffer pool information". Backporting revisions 2876.244.113,
2876.244.102 from mysql-trunk.
rb://1175 approved by Jimmy Yang.
Backporting the WL#5716, "Information schema table for InnoDB
buffer pool information". Backporting revisions 2876.244.113,
2876.244.102 from mysql-trunk.
rb://1177 approved by Jimmy Yang.
ISSUE: Incorrect key file. Key file is corrupted,
Reading incorrect key information (keyseg)
from index file. Key definition in .MYI
and .FRM file differs. Starting pointer
to read the keyseg information is changed
to a value greater than the pack_reclength.
Memcpy tries to read keyseg information from
unallocated memory which causes the crash.
SOLUTION: One more check added to compare the
the key definition in .MYI and .FRM
file. If the definition differ, server
produces an error.
primary key with innodb tables
The bug was triggered if a single ALTER TABLE statement both
added and dropped indexes and ALTER TABLE failed during drop
(e.g. because the index was needed in a foreign key constraint).
In such cases, the server index information would get out of
sync with InnoDB - the added index would be present inside
InnoDB, but not in the server. This could then lead to InnoDB
error messages and/or server crashes.
The root cause is that new indexes are added before old indexes
are dropped. This means that if ALTER TABLE fails while dropping
indexes, index changes will be reverted in the server but not
inside InnoDB.
This patch fixes the problem by dropping any added indexes
if drop fails (for ALTER TABLE statements that both adds
and drops indexes).
However, this won't work if we added a primary key as this
key might not be possible to drop inside InnoDB. Therefore,
we resort to the copy algorithm if a primary key is added
by an ALTER TABLE statement that also drops an index.
In 5.6 this bug is more properly fixed by the handler interface
changes done in the scope of WL#5534 "Online ALTER".
ISSUE: Incorrect key file. Key file is corrupted,
Reading incorrect key information (keyseg)
from index file. Key definition in .MYI
and .FRM file differs. Starting pointer
to read the keyseg information is changed
to a value greater than the pack_reclength.
Memcpy tries to read keyseg information from
unallocated memory which causes the crash.
SOLUTION: One more check added to compare the
the key definition in .MYI and .FRM
file. If the definition differ, server
produces an error.
Changes in the InnoDB codebase required to compile and
integrate the MEB codebase with MySQL 5.5.
@ storage/innobase/btr/btr0btr.c
Excluded buffer pool usage from MEB build.
buf_pool_from_bpage calls are in buf0buf.ic, and
the buffer pool functions from that file are
disabled in MEB.
@ storage/innobase/buf/buf0buf.c
Disabling more buffer pool functions unused in MEB.
@ storage/innobase/dict/dict0dict.c
Disabling dict_ind_free that is unused in MEB.
@ storage/innobase/dict/dict0mem.c
The include
#include "ha_prototypes.h"
Was causing conflicts with definitions in my_global.h
Linking C executable mysqlbackup
libinnodb.a(dict0mem.c.o): In function `dict_mem_foreign_table_name_lookup_set':
dict0mem.c:(.text+0x91c): undefined reference to `innobase_get_lower_case_table_names'
libinnodb.a(dict0mem.c.o): In function `dict_mem_referenced_table_name_lookup_set':
dict0mem.c:(.text+0x9fc): undefined reference to `innobase_get_lower_case_table_names'
libinnodb.a(dict0mem.c.o): In function `dict_mem_foreign_table_name_lookup_set':
dict0mem.c:(.text+0x96e): undefined reference to `innobase_casedn_str'
libinnodb.a(dict0mem.c.o): In function `dict_mem_referenced_table_name_lookup_set':
dict0mem.c:(.text+0xa4e): undefined reference to `innobase_casedn_str'
collect2: ld returned 1 exit status
make[2]: *** [mysqlbackup] Error 1
innobase_get_lower_case_table_names
innobase_casedn_str
are functions that are part of ha_innodb.cc that is not part of the build
dict_mem_foreign_table_name_lookup_set
function is not there in the current codebase, meaning we do not use it in MEB.
@ storage/innobase/fil/fil0fil.c
The srv_fast_shutdown variable is declared in
srv0srv.c that is not compiled in the
mysqlbackup codebase.
This throws an undeclared error.
From the Manual
---------------
innodb_fast_shutdown
--------------------
The InnoDB shutdown mode. The default value is 1
as of MySQL 3.23.50, which causes a “fast� shutdown
(the normal type of shutdown). If the value is 0,
InnoDB does a full purge and an insert buffer merge
before a shutdown. These operations can take minutes,
or even hours in extreme cases. If the value is 1,
InnoDB skips these operations at shutdown.
This ideally does not matter from mysqlbackup
@ storage/innobase/ha/ha0ha.c
In file included from /home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/ha/ha0ha.c:34:0:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/btr0sea.h:286:17: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘*’ token
make[2]: *** [CMakeFiles/innodb.dir/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/ha/ha0ha.c.o] Error 1
make[1]: *** [CMakeFiles/innodb.dir/all] Error 2
make: *** [all] Error 2
# include "sync0rw.h" is excluded from hotbackup compilation in dict0dict.h
This causes extern rw_lock_t* btr_search_latch_temp; to throw a failure because
the definition of rw_lock_t is not found.
@ storage/innobase/include/buf0buf.h
Excluding buffer pool functions that are unused from the
MEB codebase.
@ storage/innobase/include/buf0buf.ic
replicated the exclusion of
#include "buf0flu.h"
#include "buf0lru.h"
#include "buf0rea.h"
by looking at the current codebase in <meb-trunk>/src/innodb
@ storage/innobase/include/dict0dict.h
dict_table_x_lock_indexes, dict_table_x_unlock_indexes, dict_table_is_corrupted,
dict_index_is_corrupted, buf_block_buf_fix_inc_func are unused in MEB and was
leading to compilation errors and hence excluded.
@ storage/innobase/include/dict0dict.ic
dict_table_x_lock_indexes, dict_table_x_unlock_indexes, dict_table_is_corrupted,
dict_index_is_corrupted, buf_block_buf_fix_inc_func are unused in MEB and was
leading to compilation errors and hence excluded.
@ storage/innobase/include/log0log.h
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/log0log.h: At top level:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/log0log.h:767:2: error: expected specifier-qualifier-list before â⠂¬Ëœmutex_t’
mutex_t definitions were excluded as seen from ambient code
hence excluding definition for log_flush_order_mutex also.
@ storage/innobase/include/os0file.h
Bug in InnoDB code, create_mode should have been create.
@ storage/innobase/include/srv0srv.h
In file included from /home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/buf/buf0buf.c:50:0:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/srv0srv.h: At top level:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/srv0srv.h:120:16: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘srv_use_native_aio’
srv_use_native_aio - we do not use native aio of the OS anyway from MEB. MEB does not compile
InnoDB with this option. Hence disabling it.
@ storage/innobase/include/trx0sys.h
[ 56%] Building C object CMakeFiles/innodb.dir/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c.o
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c: In function ‘trx_sys_read_file_format_id’:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c:1499:20: error: ‘TRX_SYS_FILE_FORMAT_TAG_MAGIC_N’ undeclared (first use in this function)
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c:1499:20: note: each undeclared identifier is reported only once for each function it appears in
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c: At top level:
/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/include/buf0buf.h:607:1: warning: ‘buf_block_buf_fix_inc_func’ declared ‘static’ but never defined
make[2]: *** [CMakeFiles/innodb.dir/home/narayanan/mysql-server/mysql-5.5-meb-rel3.8-innodb-integration-1/storage/innobase/trx/trx0sys.c.o] Error 1
unused calls excluded to enable compilation
@ storage/innobase/mem/mem0dbg.c
excluding #include "ha_prototypes.h" that lead to definitions in ha_innodb.cc
@ storage/innobase/os/os0file.c
InnoDB not compiled with aio support from MEB anyway. Hence excluding this from
the compilation.
@ storage/innobase/page/page0zip.c
page0zip.c:(.text+0x4e9e): undefined reference to `buf_pool_from_block'
collect2: ld returned 1 exit status
buf_pool_from_block defined in buf0buf.ic, most of the file is excluded for compilation of MEB
@ storage/innobase/ut/ut0dbg.c
excluding #include "ha_prototypes.h" since it leads to definitions in ha_innodb.cc
innobase_basename(file) is defined in ha_innodb.cc. Hence excluding that also.
@ storage/innobase/ut/ut0ut.c
cal_tm unused from MEB, was leading to earnings, hence disabling for MEB.
WHEN KILLING
Suppose there is a query waiting for a lock. If the user kills
this query, then "Got error -1 when reading table" error message
must not be logged in the server log file. Since this is a user
requested interruption, no spurious error message must be logged
in the server log. This patch will remove the error message from
the log.
approved by joh and tatjana
Fixed by backport of:
------------------------------------------------------------
revno: 3402.50.156
committer: Jon Olav Hauglid <jon.hauglid@oracle.com>
branch nick: mysql-trunk-test
timestamp: Wed 2012-02-08 14:10:23 +0100
message:
Bug#13417754 ASSERT IN ROW_DROP_DATABASE_FOR_MYSQL DURING DROP SCHEMA
This assert could be triggered if an InnoDB table was being moved
to a different database using ALTER TABLE ... RENAME, while this
database concurrently was being dropped by DROP DATABASE.
The reason for the problem was that no metadata lock was taken
on the target database by ALTER TABLE ... RENAME.
DROP DATABASE was therefore not blocked and could remove
the database while ALTER TABLE ... RENAME was executing. This
could cause the assert in InnoDB to be triggered.
This patch fixes the problem by taking a IX metadata lock on
the target database before ALTER TABLE ... RENAME starts
moving a table to a different database.
Note that this problem did not occur with RENAME TABLE which
already takes the correct metadata locks.
Also note that this patch slightly changes the behavior of
ALTER TABLE ... RENAME. Before, the statement would abort and
return an error if a lock on the target table name could not
be taken immediately. With this patch, ALTER TABLE ... RENAME
will instead block and wait until the lock can be taken
(or until we get a lock timeout). This also means that it is
possible to get ER_LOCK_DEADLOCK errors in this situation
since we allow ALTER TABLE ... RENAME to wait and not just
abort immediately.
WHEN KILLING
Suppose there is a query waiting for a lock. If the user kills
this query, then "Got error -1 when reading table" error message
must not be logged in the server log file. Since this is a user
requested interruption, no spurious error message must be logged
in the server log. This patch will remove the error message from
the log.
approved by joh and tatjana
Details:
- Archive storage engine file access were not instrumented and thus
were not shown in PS tables.
Fix:
- Added instrumentation code by using PS Apis for I/O.
