Compatibility between Advanced Format-based hard drives and legacy software programs and applications is maintained through emulation, a standard AF technique designed to provide downward compatibility with host systems using legacy sector sizes.
Generation One AF emulation (or “AF 512e”) hard drives convert the data that has been written on the drive in the 4K format to 512-byte increments before transmitting the data to the host. This process, called Read-Modify-Write (RMW), eliminates the need to change a multitude of software, drivers, BIOSes and other computing ingredients that have depended on the 512-byte sector size for over 30 years.
However, realizing the full benefit from AF 512e drives requires minimizing the number of RMW operations by using components optimized for AF technology. Many newer operating systems, programs and computing elements have been designed to both recognize and accommodate AF technologies. Using AF industry-standards, these solutions provide optimal system performance when paired with AF hard drives. Computing components that simply recognize AF 512e hard drives are called “AF Aware”; those that accommodate and are optimized around AF technologies, are referred to as “AF Optimized”.
The Operating System is one of the most important elements in AF Optimized system.
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While AF 512e hard drives are compatible with all OSs, the primary way to derive maximum performance from AF 512e drives is to make sure the sector start partitions properly align with the OS and software programs. Check with your hard drive supplier to learn what solutions they use to provide proper partition alignment on their AF 512e hard drives.
Developers are encouraged to design for AF optimization. AF-based hard drives are available through the IDEMA AF Developer’s Kit Program for this purpose.