• 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

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  • 原文地址:https://www.cnblogs.com/emanlee/p/2584152.html
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