Step 1:
-- Remove page encryption from dictionary (per table
encryption will be handled by storing crypt_data to page 0)
-- Remove encryption/compression from os0file and all functions
before that (compression will be added to buf0buf.cc)
-- Use same CRYPT_SCHEME_1 for all encryption methods
-- Do some code cleanups to confort InnoDB coding style
Analysis: MySQL table definition contains also virtual columns. Similarly,
index fielnr references MySQL table fields. However, InnoDB table definition
does not contain virtual columns. Therefore, when matching MySQL key fieldnr
we need to use actual column name to find out referenced InnoDB dictionary
column name.
Fix: Add new function to match MySQL index key columns to InnoDB dictionary.
innodb_stats_sample_pages
Analysis: If you set the number of analyzed pages
to very low number compared to actual pages on
that table/index it randomly pics those pages
(default 8 pages), this leads to fact that query
after analyze table returns different results. If
the index tree is small, smaller than 10 *
n_sample_pages + total_external_size, then the
estimate is ok. For bigger index trees it is
common that we do not see any borders between
key values in the few pages we pick. But still
there may be n_sample_pages different key values,
or even more. And it just tries to
approximate to n_sample_pages (8).
Fix: (1) Introduced new dynamic configuration variable
innodb_stats_sample_traditional that retains
the current design. Default false.
(2) If traditional sample is not used we use
n_sample_pages = max(min(srv_stats_sample_pages,
index->stat_index_size),
log2(index->stat_index_size)*
srv_stats_sample_pages);
(3) Introduced new dynamic configuration variable
stat_modified_counter (default = 0) if set
sets lower bound for row updates when statistics is re-estimated.
If user has provided upper bound for how many rows needs to be updated
before we calculate new statistics we use minimum of provided value
and 1/16 of table every 16th round. If no upper bound is provided
(srv_stats_modified_counter = 0, default) then calculate new statistics
if 1 / 16 of table has been modified
since the last time a statistics batch was run.
We calculate statistics at most every 16th round, since we may have
a counter table which is very small and updated very often.
@param t table
@return true if the table has changed too much and stats need to be
recalculated
*/
#define DICT_TABLE_CHANGED_TOO_MUCH(t) \
((ib_int64_t) (t)->stat_modified_counter > (srv_stats_modified_counter ? \
ut_min(srv_stats_modified_counter, (16 + (t)->stat_n_rows / 16)) : \
16 + (t)->stat_n_rows / 16))
Merge Facebook commit 154c579b828a60722a7d9477fc61868c07453d08
and e8f0052f9b112dc786bf9b957ed5b16a5749f7fd authored
by Steaphan Greene from https://github.com/facebook/mysql-5.6
Optimize prefix index queries to skip cluster index lookup when possible.
Currently InnoDB will always fetch the clustered index (primary key
index) for all prefix columns in an index, even when the value of a
particular record is smaller than the prefix length. This change
optimizes that case to use the record from the secondary index and avoid
the extra lookup.
Also adds two status vars that track how effective this is:
innodb_secondary_index_triggered_cluster_reads:
Times secondary index lookup triggered cluster lookup.
innodb_secondary_index_triggered_cluster_reads_avoided:
Times prefix optimization avoided triggering cluster lookup.
FROM A FUNCTION
Scenario:
In a stored procedure, CREATE TABLE statement is not allowed. But an
exception is provided for CREATE TEMPORARY TABLE. We can create a temporary
table in a stored procedure.
Let there be two stored functions f1 and f2 and two stored procedures p1 and
p2. Their properties are as follows:
. stored function f1() calls stored procedure p1().
. stored function f2() calls stored procedure p2().
. stored procedure p1() creates temporary table t1.
. stored procedure p2() does DML on t1.
Consider the following situation:
1. Autocommit mode is on.
2. select f1()
3. select f2()
Step 2: In this step, t1 would be created via p1(). A table level transaction
lock would have been taken. The ::external_lock() would not have been called
on this table. At the end of step 2, because of autocommit mode on, this table
level lock will be released.
Step 3: When we execute DML on table t1 via p2() we have two problems:
Problem 1:
The function ha_innobase::external_lock() would have been called but since
it is a select query no table level locks would have been taken. Hence the
following assert will fail:
ut_ad(lock_table_has(thr_get_trx(thr), index->table, LOCK_IX));
Solution:
The solution would be to identify this situation and take a table level lock
and use the proper lock type prebuilt->select_lock_type = LOCK_X for DML
operations.
Problem 2:
Another problem is that in step 3, ha_innobase::open() is never called on
the table t1.
Solution:
The solution would be to identify this situation and call re-init the handler
of table t1.
rb#6429 approved by Krunal.
If mysql.innodb_table_stats or mysql.innodb_index_stats is not found or has
unexpected structure output that error only once and no other error for
every table trying to use them. If they do exists, then print fetch or
recalculation errors only once / table or index.
SLOW/CRASHES SEMAPHORE
Problem:
There are 2 lakh tables - fk_000001, fk_000002 ... fk_200000. All of them
are related to the same parent_table through a foreign key constraint.
When the parent_table is loaded into the dictionary cache, all the child table
will also be loaded. This is taking lot of time. Since this operation happens
when the dictionary latch is taken, the scenario leads to "long semaphore wait"
situation and the server gets killed.
Analysis:
A simple performance analysis showed that the slowness is because of the
dict_foreign_find() function. It does a linear search on two linked list
table->foreign_list and table->referenced_list, looking for a particular
foreign key object based on foreign->id as the key. This is called two
times for each foreign key object.
Solution:
Introduce a rb tree in table->foreign_rbt and table->referenced_rbt, which
are some sort of index on table->foreign_list and table->referenced_list
respectively, using foreign->id as the key. These rbt structures will be
solely used by dict_foreign_find().
rb#5599 approved by Vasil
Update InnoDB to 5.6.14
Apply MySQL-5.6 hack for MySQL Bug#16434374
Move Aria-only HA_RTREE_INDEX from my_base.h to maria_def.h (breaks an assert in InnoDB)
Fix InnoDB memory leak
SYNTAX: ATOMIC_WRITES=['DEFAULT','ON','OFF']
Idea here is to be able to define innodb_doublewrite = 1 but with following rules:
ATOMIC_WRITES='DEFAULT' - if innodb_use_atomic_writes = 1, we do not write to doublewrite buffer the changes
if innodb_use_atomic_writes = 0, we write to doublewrite buffer
ATOMIC_WRITES='ON' - do not write to doublewrite buffer
ATOMIC_WRITES='OFF' - write to doublewrite buffer
Note that doublewrite buffer can't be used if innodb_doublewrite = 0.
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)
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.
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.
With this change, the index prefix column length lifted from 767 bytes
to 3072 bytes if "innodb_large_prefix" is set to "true".
rb://603 approved by Marko
