G A L A X Y ® A U R O U R A C O N F I G U R A T I O N A N D S Y S T E M I N T E G R A T I O N G U I D E
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Section 3 Management
Reconstruction Priority (from 0 to 100):
The array is capable of
reconstructing while it is being used. This value controls the balance of priority
given to reconstruction versus the data access. The default value is 0, which
means reconstruction is only performed when the array is idle. If you set it to
100 (which is definitely not recommended), the array would run very slowly to
the clients, while reconstructing at full speed. So as an example, consider a
value of 10 - This would mean that the array would spend 10% of it's time
while being accessed, doing reconstruction. The value is up to you - the more
time and/or speed you can sacrifice while the array is being used to
reconstruction, the faster the reconstruct will complete.
Enable PQ Verification:
Default is No. This value is a form of error-detection
and correction (Raid-6 only). If this value is enabled, while the array is reading,
it will compare the data read against the two parity generators - there has to be
a 3-way match between the data and each of the two parity generators. If
there isn't, the data from the parity generators is used instead of the data from
the drive in question - this substitution is made in real-time. So basically, if the
array detects something wrong in the data, it corrects it. Enabling this option
might affect read transfer rates.
Internal Diagnostic Message Level:
More explicitly, this value determines
what you want the internal diagnostics to log. Here are the values and what
they do:
Disabled
Do not log anything.
Requests
Only log read/write requests.
State Started Only log state engine starts.
State Ended Only log state engine completions.
BIO Started Only log Block I/O starts.
BIO Ended Only log Block I/O completions.
Cache Monitor the cache.
Debug Monitor debugging.
Performance Monitor performance.
Target Monitor targets.
Silent Data Corruption
Monitor for the problem described under PQ
Verification.
