2TB WD20EARS HCL Advanced Format 4k Sectors TLER LCC WDidle3

Aligning RAID partitions Redundant array of independent disks (RAID) levels 5 and 6 have alignment issues similar to those of Advanced Format drives, but the causes relate to the size of data stripes used to create the array, typically 16KB to 256KB. When using RAID arrays, you should align partitions on multiples of the stripe size. The default alignment on 2048 sectors (1024KB) that is emerging as a new standard works well with all common RAID stripe sizes. Published test results indicate a performance penalty of about 5-30% for improper alignment, which is much less than the penalty for improperly aligning an Advanced Format drive. When creating a RAID array from Advanced Format disks, you don't need to take any extra steps. Because the RAID alignment values are multiples of the 4096-byte alignment required by Advanced Format drives, both technologies' needs are met if you align partitions as for a RAID array of disks with 512-byte physical sectors.