Dataset: Difference between revisions

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'''8. SECONDARY CACHE.'''
'''8. SECONDARY CACHE.'''


'''9. ACCESS TIME.''' The dataset can be also restricted with the Quota. The Unit is&nbsp;'''GiB.'''<br/><br/><br/>A'''ZFS reservation '''is an allocation of disk space from the pool that is guaranteed to be available to a dataset. As such, you cannot reserve disk space for a dataset if that space is not currently available in the pool. The total amount of all outstanding, unconsumed reservations cannot exceed the amount of unused disk space in the pool.<br/><br/>Additional info about quota and '''ZFS reservation''':<br/>You can use the quota property to set a limit on the amount of disk space a file system can use. In addition, you can use the reservation property to guarantee that a specified amount of disk space is available to a file system. Un-Kh properties apply to the dataset on which they are set and all descendents of that dataset.
'''9. ACCESS TIME.''' The dataset can be also restricted with the Quota. The Unit is&nbsp;'''GiB.'''<br/><br/><br/>'''10.''' A '''ZFS reservation '''is an allocation of disk space from the pool that is guaranteed to be available to a dataset. As such, you cannot reserve disk space for a dataset if that space is not currently available in the pool. The total amount of all outstanding, unconsumed reservations cannot exceed the amount of unused disk space in the pool.<br/><br/>Additional info about quota and '''ZFS reservation''':<br/>You can use the quota property to set a limit on the amount of disk space a file system can use. In addition, you can use the reservation property to guarantee that a specified amount of disk space is available to a file system. Un-Kh properties apply to the dataset on which they are set and all descendents of that dataset.

Revision as of 11:08, 5 October 2016

Creating a DATASET requires to define : 

1. NAME of the dataset. Only "a-z, A-Z, 0-9, . : _ - are allowed. 

2. DEDUPLICATION. By default the deduplication is disabled. It can be enabled by choosing the level of the deduplication :

    - ON

    - VERIFY

    - SHA256

    - SHA256, VERIFY

3. COPIES - number of copies of the data. By default it is set to 1. Other values are 2 or 3.

4. COMPRESSION. By default it is set to lz4. If the compression is not needed, it can be disabled (NONE).

5. SYNC.

6. LOG BIAS

7. PRIMARY CACHE.

8. SECONDARY CACHE.

9. ACCESS TIME. The dataset can be also restricted with the Quota. The Unit is GiB.


10. A ZFS reservation is an allocation of disk space from the pool that is guaranteed to be available to a dataset. As such, you cannot reserve disk space for a dataset if that space is not currently available in the pool. The total amount of all outstanding, unconsumed reservations cannot exceed the amount of unused disk space in the pool.

Additional info about quota and ZFS reservation:
You can use the quota property to set a limit on the amount of disk space a file system can use. In addition, you can use the reservation property to guarantee that a specified amount of disk space is available to a file system. Un-Kh properties apply to the dataset on which they are set and all descendents of that dataset.