Take the 2-minute tour ×  Is it necessary to have the partitions
that makeup a software RAID 1 array be aligned?  This guide
states  "Software RAID: Although one needs to pay attention to
correct alignment here as well, this is not explicitly necessary
as at least 64 KB-sized blocks are used."  I don't understand
how Soft RAID changes the performance hit / write amplification
issue given the underlying SSD controller is still staggering
file system pages across more than necessary flash pages.  Here
is one of my drives, I believe that the partition starting at
LBA 63, means I'm not aligned. Partitions were created via
CentOS 5 installer.  Disk /dev/sda: 120.0 GB, 120034123776 bytes
Units = sectors of 1 * 512 = 512 bytes     Device Boot
Start         End      Blocks   Id  System /dev/sda1   *
63      610469      305203+  fd  Linux raid autodetect /dev/sda2
610470    16996769     8193150   fd  Linux raid autodetect
/dev/sda3        16996770    25189919     4096575   fd  Linux
raid autodet