ZFS ensure that files are sequentially written to the cache, so SSD over-provisioning is not required.
- Go to Storage & Snapshots > Storage > Cache Acceleration.
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Click
.
The SSD Cache Introduction window opens.
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Click Start.
The Create SSD Cache window opens.
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Select one or more SSDs.
Warning:
All data on the selected disks will be deleted.
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Select a cache type.
Cache Type
Description
Read Cache
When data is read from a LUN or shared folder, QuTS hero copies the data to the SSD cache to speed up future read requests.
Read Cache and ZIL Synchronized Write Log
QuTS hero creates a read cache for accelerating read speeds, and also an SSD ZFS intent log (ZIL). The SSD ZIL is not a true write cache, but it can help accelerate random write performance.
- Click Next.
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Select which shared folders and LUNs can use the SSD cache.
Tip:
This list can be modified later.
- Click Next.
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Select a cache mode.
Cache Mode
Description
Recommended Use Cases
Random I/O
Only small data blocks are added to the SSD cache. Larger blocks are accessed directly from regular storage.
Virtualization, databases
All I/O
Small and large data blocks are added to the SSD cache. Both sequential and random I/O requests are accelerated.
Video streaming, large file access operations
Tip:An HDD RAID group may outperform a SSD RAID group for sequential I/O if the ratio of HDDs to SSDs is 3:1 or greater, and the HDD group has a RAID type of RAID 0, 5, 6, or 10. However, SSDs will always be faster for random I/O. If the NAS contains a RAID group of type RAID 0, 5, 6, or 10 that contains three times more disks than the SSD cache, you should select Random I/O.
- Click Next.
- Review the summary information.
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Click Create.
A confirmation message appears.
- Select I understand and then click OK.