Oracle 5.0 Reference Manual page 1271

InnoDB
replication master server unless you have an unusual setup where only one thread is able to change
data.
For a server that is accepting data changes from only one thread, it is safe and recommended to
turn off this option to improve performance for
replication slaves where only the replication SQL thread is changing data.
You can also turn off this option if you do not need it for safe binary logging or replication, and you
also do not use an external XA transaction manager.
This variable was added in MySQL 5.0.3.
•
innodb_sync_spin_loops
Version Introduced
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
The number of times a thread waits for an
suspended. The default value is 20. This variable was added in MySQL 5.0.3.
•
innodb_table_locks
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
If
autocommit = 0
TABLES ... WRITE
value of
innodb_table_locks
lock a table internally if
•
innodb_thread_concurrency
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
Startup Options and System Variables
5.0.3
--innodb_sync_spin_loops=#
innodb_sync_spin_loops
Yes,
innodb_sync_spin_loops
innodb_sync_spin_loops
Global
Yes
InnoDB
--innodb_table_locks
innodb_table_locks
Yes,
innodb_table_locks
innodb_table_locks
Global, Session
Yes
Permitted Values
Type
boolean
Default
TRUE
[436], honors
InnoDB LOCK
until all other threads have released all their locks to the table. The default
[1251] is 1, which means that
[436].
autocommit = 0
--innodb_thread_concurrency=#
innodb_thread_concurrency
Yes,
innodb_thread_concurrency
innodb_thread_concurrency
Global
Yes
Permitted Values (>= 5.0.9)
1251
tables. For example, you can turn it off on
InnoDB
[1251]
mutex to be freed before the thread is
[1251]
TABLES; MySQL does not return from
LOCK TABLES
[1251]
LOCK
causes InnoDB to