Dell EMC H740P - Configuring Virtual Disk Policies; Configuring Virtual Disks Based on Workload

Conguring virtual disk policies
1 Enter the Dell PERC 10 Conguration Utility. See Navigating to Dell PERC 10 conguration utility.
2 Click Main Menu > Virtual Disk Management.
All the virtual disks associated with the RAID controller are displayed.
3 Click Advanced....
You can view the following virtual disk policies:
Table 10. Virtual disk policies
Option Description
Current write cache Indicates the current write cache policy for the virtual disk.
Default write cache Allows selection of the write cache policy for the virtual disk. The
possible options are:
• Write Through
• Write Back
• Force Write Back
Read Cache policy Allows selection of the read cache policy for the virtual disk. The
possible options are:
• No Read Ahead
• Read Ahead
Disk Cache Allows selection of the disk cache policy for the virtual disk. The
possible options are:
• Default (Disk Default)
• Enable
• Disable
4
Click Apply Changes.
The changes made are saved successfully.
Conguring Virtual Disks
When conguring the virtual disks, you should consider the workload intended; RAID1: for simple boot disk; RAID5 or 6: for le or web
servers (sequential reads/writes of les); RAID10: for transactional database (small random reads and writes).
Virtual disks congured on hard drives should use the controller default cache setting of Write Back and Read Ahead.
Virtual disks congured on SSDs can use the same controller defaults settings as hard drives. Most users perform a copy of OS les or a
data base to the new array. This setting provides optimum performance in this conguration.
Once the copy is complete, the array can be used as it is depending on the number and type of SSDs. It is recommended to enable
FastPath by changing the controller's Write cache policy to Write Through and the Read cache policy to No Read Ahead. FastPath is
developed to achieve the best random read/write performance from SSDs.
Only IO block sizes smaller than the virtual disk's stripe size are eligible for FastPath. In addition, there should be no background operations
(rebuild, initialization) running on the virtual disks. FastPath is disabled if there is active background operation.
NOTE
: RAID 50, and RAID 60 virtual disks cannot use FastPath.
54 HII conguration utility