NEC Express5800 Series Maintenance Manual page 111

Chapter 2 Useful Features
5) Specify values for Virtual Drive Name, Virtual Drive Size, Virtual Drive Size Unit, Disk
WC, and Read Ahead.
5-1. Virtual Drive Name: Specify the name of the virtual drive. (Optional).
5-2. Virtual Drive Size: specifies the capacity of the virtual drive.
5-3. Virtual Drive Size Unit: Specify the unit (MB/GB/TB) used for Virtual Drive Size.
5-4. Disk WC: Specify the Disk Write Cache policy.
Parameter
Enable* Write back
Disable Write through
*
For this server, Setting "Enable" is recommended
for good performance. Note, however, that cached
data may be lost at an unexpected power failure.
Selecting "Disable" degrades performance by
approximately 50%, comparing with the "Enable"
setting.
5-5. Read Ahead: Specify the Read Ahead setting.
Parameter
Disable
Enable*
Express5800/B120f-h Maintenance Guide
Remarks
* Recommended
Remarks
Does not perform read ahead.
Performs read ahead.
* Recommended
4. RAID System Configuration
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