QNAP TVS-472XT 4-Bay NAS Enclosure - Manual (Page 115)

Depending on the model you may be asked to power off then power on the device, or disconnect then
reconnect the device.
QTS re-detects the device and displays a notification message.
3. Wait for confirmation that the firmware update has finished.
4. Go to Storage & Snapshots > Storage > Disks/VJBOD .
5. Click Recover, and then select Attach and Recover Storage Pool.
Qtier
Qtier is a proprietary automated-tiering technology, designed to increase NAS storage performance and
reduce the total cost of NAS ownership.
With Qtier, a storage pool can contain a mixture of solid-state drives (SSDs), hard disk drives (HDDs), and
Serial Attached SCSI (SAS) drives. QTS creates a separate storage tier for each disk type, and then moves
data between the tiers based on access frequency. Frequently accessed data is moved to the fastest disks for
greater read and write performance. Infrequently accessed data is moved to the slower high-capacity disks
for more cost effective data storage.
Qtier Benefits
NAS
Configuration
Cost Storage
Capacity
Read/Write
Performance
Management Effort
All HDDs Low High Low Low
All SSDs Very high Low High Low
SSDs and HDDs
manually
separated into
two or more
storage pools
Moderate Medium High for SSD
pool, low for
HDD pool
High (admin must
manually move data
between pools)
Qtier with SSDs
and HDDs in
one Qtier-
enabled storage
pool
Moderate Medium High for
frequently
accessed data
Low (QTS automatically
moves data between
disks)
Qtier 2.0 IO Aware
Qtier 2.0 IO Aware is a feature available in QTS version 4.3.3 or later. With IO Aware, QTS reserves 25% of
the SSD tier capacity in a Qtier storage pool for faster access performance. If data in the capacity or high
speed tiers experiences a high number of read or write requests, QTS immediately moves it to reserved
SSD space instead of waiting to move it using auto-tiering. This improves random I/O performance, offering
performance similar to having an SSD cache.
Qtier and SSD Cache Comparison
Note
Qtier can be used at the same time as SSD cache.
There are three main configuration options when configuring a NAS with a mixture of HDDs and SSDs.
QTS 4.4.x User Guide
Storage & Snapshots 114