Asus PCI-DA2100 User Manual - Page 23

3 IMPORTANT: The "Verification on LD Normal Drive Writes" method will affect "write" performance during normal use. 3.4 Cache Parameters 3.4.1 Optimization for Sequential or Random I/O When using RAID with applications such as video or image oriented applications, the application reads/writes from the drive using largeblock, sequential files instead of small-block, random access files. The ASUS PCI-DA2100/-DA2200 RAID controller provides the options to optimize for large-sequential I/O or optimize for small-random I/O access. "Optimization for Sequential I/O" provides a larger - 128K - stripe size (or "block" size, also known as "chunk" size) than does "Optimization for Random I/O" (with a size of 32K). A lot of the controller's internal parameters will also be changed to optimize for sequential or random I/O. The change will take effect after the controller reboots. If the existing logical drives were built with "Optimization for Random I/O", these logical drives will not read/write when using "Optimization for Sequential I/O" (shows "INVALID") and vice versa because the stripe size is different. Change it back to the original setting and reset the controller to make available the logical drive data again. IMPORTANT: Changing the setting to "Optimization for Sequential I/O" or "Optimization for Random I/O" should be performed only when no logical drive exist. Otherwise, you will not be able to access the data in the logical drive later on. ASUS PCI-DA2100/PCI-DA2200 User's Manual 23