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vmcj/nested_lock_loops - max loops to get a nested lock

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| Parameter : vmcj/nested_lock_loops                                   |

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| Short description : Maximum number of loops to get a nested lock     |

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| Parameter description :                                              |

| -----------------------                                              |

| When requesting cross-VM locks (shared locks), the following needs   |

| to be taken into account:                                            |

| - If another shared lock is requested within an area protected by a  |

|   by a shared lock, deadlocks can occur if the lock sequence is      |

|   incorrect                                                          |

| - If cross-VM Garbage Collection is active, a VM that is requesting  |

|   a shared lock may first have to contribute to the Garbage          |

|   Collection before it can obtain the shared lock.                   |

|   To allow this, the lock request must not block. If a timeout       |

|   occurs at the first attempt to obtain the lock, the VM enters a    |

|   loop in which control is briefly released and it then attempts to  |

|   obtain the lock again.                                             |

|                                                                      |

|                                                                      |

| Parameter vmcj/nested_lock_loops allows you to limit the number of   |

| loop passes:                                                         |

|                                                                      |

| -1:   An infinite number of attempts are made to set the lock        |

|       (no limit). This is the default.                               |

| >= 0: Maximum number of attempts to obtain the lock. Each attempt    |

|       lasts approximately 1 second. If it has still not been         |

|       possible to set the lock after the n lock attempts have been   |

|       made, the lock request is rejected.                            |

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| Application Area : VMC                                               |

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| Unit : Number greater than or equal to -1                            |

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| Default value: -1                                                    |

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| Who is permitted to make changes : The customer                      |

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| Limitations for operating systems: None                              |

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| Limitations for database systems: None                               |

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| Other parameters affected or dependent: None                         |

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| Valid Input, Formats, Areas:                                         |

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| Short Description : max loops to get a nested lock 

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| Applications Area : VMC 

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| Parameter Type : I 

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| Changes allowed : X 

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| Valid for Operating System : * 

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| Dynamic switchable : X 

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| Same on all Servers :  

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