Oracle 10 参数配置说明
semsys:seminfo_semmni
Description
Maximum number of semaphore identifiers.
Data Type
Signed integer
Default
10
Range
1 to 65,535
Dynamic?
No
Validation
Compared to SEMA_INDEX_MAX (currently 65,535) and reset to that value if larger. A warning message is written to the console and or system messages file.
When to Change
When the default number of sets is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to create more sets than are currently configured. The application sees a return code of ENOSPC from a semget(2) call.
Commitment Level
Unstable
semsys:seminfo_semmns
Description
Maximum number of System V semaphores on the system.
Data Type
Signed integer
Default
60
Range
1 to MAXINT
Dynamic?
No
Validation
The amount of space that could possibly be consumed by the semaphores and their supporting data structures is compared to 25% of the kernel memory available at the time the module is first loaded. If the memory threshold is exceeded, the module refuses to load and the semaphore facility is not available.
When to Change
When the default number of semaphores is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to create more semaphores than are currently configured. The application sees a return code of ENOSPC from a semget(2) call.
Commitment Level
Unstable
semsys:seminfo_semvmx
Description
Maximum value a semaphore can be set to.
Data Type
Unsigned short
Default
32,767
Range
1 to 65,535
Dynamic?
No
Validation
None
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when the maximum value is exceeded. The application sees a return code of ERANGE from a semop(2) call.
Commitment Level
Unstable
semsys:seminfo_semmsl
Description
Maximum number of System V semaphores per semaphore identifier.
Data Type
Signed integer
Default
25
Range
1 to MAXINT
Dynamic?
No
Validation
The amount of space that could possibly be consumed by the semaphores and their supporting data structures is compared to 25% of the kernel memory available at the time the module is first loaded. If the memory threshold is exceeded, the module refuses to load and the semaphore facility is not available.
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to create more semaphores in a set than are currently configured. The application sees a return code of EINVAL from a semget(2) call.
Commitment Level
Unstable
semsys:seminfo_semopm
Description
Maximum number of System V semaphore operations per semop(2) call. This parameter refers to the number of sembufs in the sops array that is provided to the semop() system call.
Data Type
Signed integer
Default
10
Range
1 to MAXINT
Dynamic?
No
Validation
The amount of space that could possibly be consumed by the semaphores and their supporting data structures is compared to 25% of the kernel memory available at the time the module is first loaded. If the memory threshold is exceeded, the module refuses to load and the semaphore facility is not available.
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to perform more semaphore operations in a single semop call than are currently allowed. The application sees a return code of E2BIG from a semop() call.
Commitment Level
Unstable
semsys:seminfo_semmnu
Description
Total number of undo structures supported by the System V semaphore system.
Data Type
Signed integer
Default
30
Range
1 to MAXINT
Dynamic?
No
Validation
The amount of space that could possibly be consumed by the semaphores and their supporting data structures is compared to 25% of the kernel memory available at the time the module is first loaded. If the memory threshold is exceeded, the module refuses to load and the semaphore facility is not available.
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error message is displayed when an attempt is made to perform more undo operations than are currently configured. The application sees a return value of ENOSPC from a semop(2) call when the system runs out of undo structures.
Commitment Level
Unstable
Changes From Previous Release
For information, see semsys:seminfo_semmnu.
semsys:seminfo_semume
Description
Maximum number of System V semaphore undo structures that can be used by any one process.
Data Type
Signed integer
Default
10
Range
1 to MAXINT
Dynamic?
No
Validation
The amount of space that could possibly be consumed by the semaphores and their supporting data structures is compared to 25% of the kernel memory available at the time the module is first loaded. If the memory threshold is exceeded, the module refuses to load and the semaphore facility is not available.
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to perform more undo operations than are currently configured. The application sees a return code of EINVAL from a semop(2) call.
Commitment Level
Unstable
semsys:seminfo_semaem
Description
Maximum value that a semaphore's value in an undo structure can be set to.
Data Type
Unsigned short
Default
16,384
Range
1 to 65,535
Dynamic?
No
Validation
None
When to Change
When the default value is not enough. Generally changed at the recommendation of software vendors. No error messages are displayed when an attempt is made to perform more undo operations than are currently configured. The application sees a return code of EINVAL from a semop(2) call.
Commitment Level
Unstable
http://docs.oracle.com/cd/E19683-01/806-7009/chapter2-70/index.html
