Oracle 5.0, Reference Manual

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InnoDB
Startup Options and System Variables
1238
that are created if you use
innodb_file_per_table=1
[1241] . Those files are auto-extending
regardless of the value of
innodb_autoextend_increment
[1237] . The initial extensions are by
small amounts, after which extensions occur in increments of 4MB.
•
innodb_buffer_pool_awe_mem_mb
Command-Line Format
--innodb_buffer_pool_awe_mem_mb=#
Option-File Format
innodb_buffer_pool_awe_mem_mb
Option Sets Variable Yes,
innodb_buffer_pool_awe_mem_mb
[1238]
Variable Name
innodb_buffer_pool_awe_mem_mb
Variable Scope Global
Dynamic Variable No
Platform Specific windows
Permitted Values
Type
(windows)
numeric
Default
0
Range
0 .. 63000
The size of the buffer pool (in MB), if it is placed in the AWE memory. If it is greater than 0,
innodb_buffer_pool_size
[1238] is the window in the 32-bit address space of
mysqld
where
InnoDB
maps that AWE memory. A good value for
innodb_buffer_pool_size
[1238] is 500MB.
The maximum possible value is 63000.
To take advantage of AWE memory, you will need to recompile MySQL yourself. The current project
settings needed for doing this can be found in the
innobase/os/os0proc.c
source file.
This variable is relevant only in 32-bit Windows. If your 32-bit Windows operating system supports
more than 4GB memory, using so-called “Address Windowing Extensions,” you can allocate the
InnoDB
buffer pool into the AWE physical memory using this variable.
•
innodb_buffer_pool_size
Command-Line Format
--innodb_buffer_pool_size=#
Option-File Format
innodb_buffer_pool_size
Option Sets Variable Yes,
innodb_buffer_pool_size
[1238]
Variable Name
innodb_buffer_pool_size
Variable Scope Global
Dynamic Variable No
The size in bytes of the memory buffer
InnoDB
uses to cache data and indexes of its tables. The
default value is 8MB. The larger you set this value, the less disk I/O is needed to access data in
tables. On a dedicated database server, you may set this to up to 80% of the machine physical
memory size. However, do not set it too large because competition for physical memory might cause
paging in the operating system. Also, the time to initialize the buffer pool is roughly proportional to its
size. On large installations, this initialization time may be significant. For example, on a modern Linux
x86_64 server, initialization of a 10GB buffer pool takes approximately 6 seconds. See
Section 8.6.2,
“The
InnoDB
Buffer Pool”
•
innodb_checksums
Version Introduced 5.0.3
Command-Line Format
--innodb_checksums