XEVO
Software Manual
Storage Tab
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CAUTION
Models with XEVO do NOT support disk roaming from models with SANOS.
5.6.
SSD Cache
SSD cache allows an SSD to function as read cache or write buffer for a HDD volume. In SSD
read cache, it is a secondary cache that improves performance by keeping frequently accessed
data on SSDs where they are read far more quickly than from the HDD volume. When reads or
writes are performed, the data from the HDDs are copied into the SSD cache. Although the data
is duplicated to SSD cache pool, it does not matter if the read cache pool is corrupted.
In SSD write cache, SSDs are a write buffering storage that improves performance by storing the
write data in SSDs temporary where they are write far more quickly than to the HDD volume.
And then the write data will be flushed to the HDD volume at the appropriate time. It may take
risk of losing data during the period that the write data is stored in SSD cache if the SSD cache
pool is corrupted. The write data has not yet written back to the HDD volume. So the read-write
cache pool needs data protection to protect the write data.
CAUTION
Using SSD read-write cache may take risk of losing data if the SSD cache pool
is corrupted. User has to monitor the health of the SSD cache pool carefully.
For detailed information, please refer to the
5.7.
Auto Tiering
Auto tiering is the automated progression or demotion of data across different tiers (types) of
storage devices and media. The movement of data takes place in an automated way with the
help of software and is assigned to the ideal storage media according to performance and
