Iomega StorCenter ix12 User Manual page 81

81 Iomega StorCenter ix12
Drive Management
The Drive Management page manages drive information and write caching for your Iomega StorCenter ix12.
Write caching is a mechanism that attempts to separate the fast processing speed of the Iomega StorCenter ix12 from the relatively slow mechanics of
actually writing data to drive.
With write caching disabled, every write to drive will cause the Iomega StorCenter ix12 to wait while the data is written to drive, which can slow performance.
When write caching is enabled and the Iomega StorCenter ix12 sends a write request to the drive, instead of writing directly to the drive, it writes the data to
cache (which is much faster) and sends an immediate acknowledgement to the Iomega StorCenter ix12 saying the write is complete. The system can then
proceed without having to wait for the data to actually get written to drive, which will occur in the background.
While write caching does improve performance, there are some risks. Because the system will respond that the data has been written to drive when in fact it
has only been written to cache, should the Iomega StorCenter ix12 lose power any data that did not get completely written to drive will be lost forever. This is
because cache memory is volatile. Therefore, if you lose power during a write, any pending writes in the cache that were not written to the drive yet will be
lost forever. Using a UPS (Uninterrupted Power Supply) can mitigate the risk associated with write caching, which is why it is recommended to only enable this
feature when a UPS is connected.
Click Apply to save your changes.