Hard Drive Notes

SATA drives must be in Advanced Host Controller Interface (AHCI) for Native Command Queuing (NCQ) to work.
http://www.brighthub.com/computing/hardware/articles/23013.aspx
IIRC, I did this once to enable AHCI in Win7 after installation as ATA: http://support.microsoft.com/kb/922976
I tried but failed on XP with these: http://www.blah-blah.ch/it/how-to-s/enable-ahci/
MSKB on this - change these two registry keys to 0 to enable the driver - Vista and Win7 - http://support.microsoft.com/kb/922976
- HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci\Start
- HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\IastorV\Start
- I've seen a different post say this, maybe for XP: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Pciide\Start
Linux has a "writemostly" mode which will generally direct reads to one (faster) part of a RAID set (i.e. SSD). Originally for network RAID. - http://tansi.info/hybrid/

Benchmark

Basic HDD benchmark tool built into recent versions of Windows (run as administrator to keep command window sane, or use log option): winsat disk -drive c

Advanced Format (AF)

Supported in Vista, Server 2008 and newer (with service packs/updates).
Win7 needs this update to add "Bytes per Physical Sector" to this command:
- fsutil fsinfo ntfsinfo C:
  - 512B is legacy. 4KB is advanced format.
- https://support.microsoft.com/en-ca/kb/982018
This is NOT the same as "4KB Native"... "For hard disk drives working in the 4K native mode, there is no emulation layer in place, and the disk media directly exposes its 4096, 4112, 4160, or 4224-byte physical sector size to the system firmware and operating system. That way, the externally visible logical sectors organization of the 4K native drives is directly mapped to their internal physical sectors organization." -- wikipedia.
Check alignment to 4KB sectors - "Check the start sector values. A properly-aligned partition will have a start sector value that's a multiple of 8. In this example.... In the case of MBR disks, ignore any "misalignment" of extended partitions; only primary and logical partitions need to be properly aligned." - http://superuser.com/questions/686322/the-partition-is-misaligned-by-512-bytes - GParted shows start sectors nicely.

RAID Alternatives

Some random names, while searching for something to provide redundancy while using all the disk space (when drives are mismatched).

Good thread: https://ask.slashdot.org/story/12/05/03/1915230/ask-slashdot-diy-nas-for-a-variety-of-legacy-drives

flexraid - software based, proprietary
Windows Storage Spaces (Server 2012)
FreeNAS (with ZFS and some configuration)
unraid - software based, proprietary
greyhole - works at file level with samba - somehow makes sure there is always multiple copies of a file (will this work on huge files?)
btfrs "RAID-1" is at the block level - it will use random sized drives efficiently - https://stackoverflow.com/questions/23620964/btrfs-raid1-with-multiple-devices/23621137#23621137

tags: drive, disk, hdd, sata, !achi,