Compaq Infortrend Optimization for Random or Sequential I/O, Optimization for Sequential I/O?

Optimization for Random or Sequential I/O

Select from main menu “View and Edit Config Parms,” “Caching Parameters,” and press ENT. Choose “Optimization for Random I/O” or “Optimization for Sequential I/O,” then press ENT for two seconds to confirm. Press ESC to leave and the setting will take effect after the controller is restarted.

Caching

Parameters ..

Optimization I/O

Random ..

Optimization for Sequential I/O?

IMPORTANT!

•The original 512GB threshold on array optimization mode is canceled. If the size of an array is larger than 16TB, only the optimization for sequential I/O can be applied. Logical drives of this size are not practical; therefore, there is actually no limitation on the optimization mode and array capacity.

Write-Back/Write-Through Cache Enable/Disable

As one of the submenus in "Caching Parameters," this option controls the cached write function. Press ENT to enable or disable “Write-Back Cache.” Press ENT for two seconds to confirm. The current status will be displayed on the LCD.

The Write-through mode is safer if your controller is not configured in a redundant pair and there is no battery backup.

Write-Back Cache

Enabled ..

Disable Write
-Back Cache	?

Write-back caching can dramatically improve write performance by caching the unfinished writes in memory and let them be committed to drives in a more efficient manner. In the event of power failure, a battery module can hold cached data for days. In the event of controller failure, data cached in the failed controller has an exact replica on its counterpart controller and therefore remains intact.

Front Panel Operation 5-3