The counter handler_read_key (SSV::ha_read_key_count) is incremented
incorrectly.
The mysql server maintains a per thread system_status_var (SSV)
object. This object contains among other things the counter
SSV::ha_read_key_count. The purpose of this counter is to measure the
number of requests to read a row based on a key (or the number of
index lookups).
This counter was wrongly incremented in the
ha_innobase::innobase_get_index(). The fix removes
this increment statement (for both innodb and innodb_plugin).
The various callers of the innobase_get_index() was checked to
determine if anybody must increment this counter (if they first call
innobase_get_index() and then perform an index lookup). It was found
that no caller of innobase_get_index() needs to worry about the
SSV::ha_read_key_count counter.
This bug ensures that a live downgrade from an InnoDB 5.6 with WL5756 and
a database created with innodb-page-size=8k or 4k will make a version 5.5
installation politely refuse to start. Instead of crashing or giving some
indication about a corrupted database, it will indicate the page size
difference.
This patch takes only that part of the Wl5756 patch that is needed to
protect against opening a tablespace that is stamped with a different
page size.
It also contains the change in dict_index_find_on_id_low() just in case
a database with another page size is created by recompiling a pre-WL5756
InnoDB.
WITH LARGE BUFFER POOL
(Note: this a backport of revno:3472 from mysql-trunk)
rb://845
approved by: Marko
When dropping a table (with an .ibd file i.e.: with
innodb_file_per_table set) we scan entire LRU to invalidate pages from
that table. This can be painful in case of large buffer pools as we hold
the buf_pool->mutex for the scan. Note that gravity of the problem does
not depend on the size of the table. Even with an empty table but a
large and filled up buffer pool we'll end up scanning a very long LRU
list.
The fix is to scan flush_list and just remove the blocks belonging to
the table from the flush_list, marking them as non-dirty. The blocks
are left in the LRU list for eventual eviction due to aging. The
flush_list is typically much smaller than the LRU list but for cases
where it is very long we have the solution of releasing the
buf_pool->mutex after scanning 1K pages.
buf_page_[set|unset]_sticky(): Use new IO-state BUF_IO_PIN to ensure
that a block stays in the flush_list and LRU list when we release
buf_pool->mutex. Previously we have been abusing BUF_IO_READ to achieve
this.
WITH MYISAM_USE_MMAP ENABLED
MySQL server can crash due to segmentation fault when
started with myisam_use_mmap.
The reason behind this being, while making a request to
unmap (munmap) the previously mapped memory (mmap), the
size passed was 7 bytes larger than the size requested at
the time of mapping. This can eventually unmap the adjacent
memory mapped block, belonging to some other memory-map pool.
Hence the subsequent call to mmap can map a region which was
still a valid memory mapped area.
Fixed by removing the extra 7-byte margin which was erroneously
added to the size, used for unmappping.
storage/myisam/mi_close.c:
Bug#11756764 48726: MYSQLD KEEPS CRASHING WITH SIGSEGV
WITH MYISAM_USE_MMAP ENABLED
Added a condition to call _mi_unmap_file() in case
of compressed records. mi_munmap_file() is called
otherwise.
storage/myisam/mi_packrec.c:
Bug#11756764 48726: MYSQLD KEEPS CRASHING WITH SIGSEGV
WITH MYISAM_USE_MMAP ENABLED
mi_dynmap_file() function, after successfully executing
mmap, stores the total size in info->s->mapped_length
variable. Now, if mi_dynmap_file() is invoked with a size
with an extra 7-byte margin (MEMMAP_EXTRA_MARGIN),
the margin will eventually also get stored in mapped_length.
So, un-mapping function can simply use the value stored in
mapped_length in order to unmap the previously mapped
region.
AND HANG IN SHOW TABLE STATUS.
ISSUE: Table corruption due to concurrent queries.
Different threads running insert and check
query leads to table corruption. Not properly locked,
rows are inserted in between check query.
SOLUTION: In check query mutex lock is acquired
for a longer time to handle concurrent
insert and check query.
NOTE: Additionally we backported the fix for CHECKSUM
issue(bug#11758979).
Remove btr_cur_t::ibuf_cnt. The only dependence on cursor->ibuf_cnt
was ibuf_set_entry_counter(). That code path was removed in the
original bug fix (marko.makela@oracle.com-20111107072802-dgwagejlpub0rjkd).
rb:819 approved by Jimmy Yang
rb://816
approved by: Marko Makela
The title is misleading. This bug was actually introduced by
bug 12635227 and was unearthed by a later optimization.
We need to free buf_page_t structs that we are allocating using
malloc() at shutdown.
I manually checked that all the conflicting InnoDB changes are in 5.5 already.
Two things I am not sure about - I commented them with XXX in this patch.
I will further check with the authors of the changesets whether these things
should be present or not.
a.k.a. Bug#7975 deadlock without any locking, simple select and update
Bug#7975 was reintroduced when the storage engine API was made
pluggable in MySQL 5.1. Instead of looking at thd->lex directly, we
rely on handler::extra(). But, we were looking at the wrong extra()
flag, and we were ignoring the TRX_DUP_REPLACE flag in places where we
should obey it.
innodb_replace.test: Add tests for hopefully all affected statement
types, so that bug should never ever resurface. This kind of tests
should have been added when fixing Bug#7975 in MySQL 5.0.3 in the
first place.
rb:806 approved by Sunny Bains
btr_pcur_restore_position_func(): When the cursor was positioned at
the tree infimum or supremum, initialize pos_state and latch_mode. The
assertion failed, because pos_state was BTR_PCUR_WAS_POSITIONED. In
the test failure of WL#5874, the purge thread attempted to restore the
cursor position on the infimum record (the clustered index was empty).
btr_pcur_detach(), btr_pcur_is_detached(): Unused functions, remove.
rb:804 approved by Inaam Rana
ibuf_insert_low(), the only caller of ibuf_set_entry_counter(), will
have latched an insert buffer bitmap page in bitmap_mtr before
invoking ibuf_set_entry_counter(). The latching order forbids any
further pages to be latched.
ibuf_set_entry_counter(): Renamed to ibuf_get_entry_counter(),
simplified the code and added comments.
Added the following symbols for predefined field numbers in change
buffer records:
#define IBUF_REC_FIELD_SPACE 0 /*!< in the pre-4.1 format,
the page number. later, the space_id */
#define IBUF_REC_FIELD_MARKER 1 /*!< starting with 4.1, a marker
consisting of 1 byte that is 0 */
#define IBUF_REC_FIELD_PAGE 2 /*!< starting with 4.1, the
page number */
#define IBUF_REC_FIELD_METADATA 3 /* the metadata field */
#define IBUF_REC_FIELD_USER 4 /* first user field */
rb:802 approved by Sunny Bains
row_rename_table_for_mysql(): Return DB_ERROR instead of DB_SUCCESS
when fil_rename_tablespace() returns an error. This bug was introduced
in the InnoDB Plugin.
Approved by Sunny Bains over IM.
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.
This was an attempt to address problems with the Bug#12612184 fix.
Even with this follow-up fix, crash recovery can be broken.
Let us fix the bug later.
In the ON UPDATE CASCADE clause of FOREIGN KEY constraints, the
calculated update vector was not fully initialized. This bug was
introduced in the InnoDB Plugin when implementing support for
ROW_FORMAT=DYNAMIC.
Additionally, the data type information was not initialized, but
apparently it has never been needed in this case. Nevertheless, it is
not good programming practice to pass uninitialized values around.
calc_row_difference(): Declare the update field uninitialized in
Valgrind. Copy the data type information as well, except when the
field is SQL NULL. In the built-in InnoDB, initialize
ufield->extern_storage = FALSE (an initialization bug that had gone
unnoticed this far). The InnoDB Plugin and later have this flag to
dfield_t and have always initialized it properly.
row_ins_cascade_calc_update_vec(): Reduce the scope of some
pointers. Initialize orig_len. (This caused the bug in InnoDB Plugin
and later.)
row_ins_foreign_check_on_constraint(): Simplify a condition. Declare
the update vector uninitialized.
rb:771 approved by Jimmy Yang
TESTS: CRASH, CORRUPTION, 4G MEMOR
Issue: Valgrind errors due to checksum and optimize
query against archive tables with null columns.
Table record buffer was not initialized.
Solution: Initialize the record buffer.
TESTS: CRASH, CORRUPTION, 4G MEMOR
Issue: Valgrind errors due to checksum and optimize
query angaist archive tables with null columns.
Table record buffer was not initialized.
Solution: Initialize the record buffer.
btr_record_not_null_field_in_rec(): Remove the parameter rec.
Use rec_offs_nth_sql_null() instead of rec_get_nth_field().
rb:788 approved by Jimmy Yang
USING MYISAM_USE_MMAP ON WINDOWS
When OPTIMIZE/REPAIR TABLE is switching to new data file,
old data file is removed while memory mapping is still
active.
With 5.1 implementation of nt_share_delete() it is not
permitted to remove mmaped file.
This fix disables memory mapping for mi_repair() operations.
mysql-test/r/myisam.result:
A test case for BUG#11757032.
mysql-test/t/myisam.test:
A test case for BUG#11757032.
storage/myisam/ha_myisam.cc:
mi_repair*() functions family use file I/O even if memory
mapping is available.
Since mixing mmap I/O and file I/O may cause various artifacts,
memory mapping must be disabled.
storage/myisam/mi_delete_all.c:
Clean-up: do not attempt to remap file after truncate, since
there is nothing to map.
