Cache flush modifier, Cache without battery enabled, Modification priority – Dell PowerVault MD3420 User Manual
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Cache Flush Modifier
Valid values for the cache flush modifier are listed in the following table.
Value
Description
Immediate
Data is flushed as soon as it is placed into the
cache.
250
Data is flushed after 250 ms.
500
Data is flushed after 500 ms.
750
Data is flushed after 750 ms.
1
Data is flushed after 1 s.
1500
Data is flushed after 1500 ms.
2
Data is flushed after 2 s.
5
Data is flushed after 5 s.
10
Data is flushed after 10 s.
20
Data is flushed after 20 s.
60
Data is flushed after 60 s (1 min.).
120
Data is flushed after 120 s (2 min.).
300
Data is flushed after 300 s (5 min.).
1200
Data is flushed after 1200 s (20 min.).
3600
Data is flushed after 3600 s (1 hr).
Infinite
Data in cache is not subject to any age or time
constraints. The data is flushed based on other
criteria that are managed by the RAID controller
module.
Cache Without Battery Enabled
Write caching without batteries enables write caching to continue if the RAID controller module batteries
are completely discharged, not fully charged, or not present. If you set this parameter to TRUE without an
uninterruptible power supply (UPS) or other backup power source, you can lose data if the power to the
storage array fails. This parameter has no effect if write caching is disabled.
Modification Priority
Modification priority defines the amount of system resources that are used when modifying virtual disk
properties. If you select the highest priority level, the virtual disk modification uses the most system
resources, which decreases the performance for host data transfers.
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