AHCI or IDE?

[globus999]

Hi,
Running FN 8.0.1 Beta 4 64-bits.
Currently the BIOS is set up as IDE, but I have the option to set it up as AHCI.
IDE seems to be working OK, so far (have not yet tested exhaustively) but I understand AHCI provides further improvement.
However, googling away it would seem that the advantages are somewhat of a hit-and-miss.
I don't want to screw-up my system since it contains a lot of data.
Should I enable AHCI or leave it at IDE?
Appreciated!

 

[joeschmuck]

I don't believe shifting over to AHCI will cause you to lose any data but I would have it all backed up myself. Everything I've read doesn't care if it's IDE or AHCI but I did find this one thing:
"One benefit to use the AHCI drives is that it supports NCQ and if your drives do (all new drives do), you will benefit for random and multitask IO. "

Not sure if this would factor in for your particular use. I unfortunately cannot test this out since my MB doesn't support AHCI.

My advice is to leave it at IDE if you're happy with your system performance. Last thing, if you were to upgrade to a new version of FreeNAS, let's say Beta 5, and you lost all your data, would you be able to recover all your important data? I ask because keep in mind we are still at Beta and it is possible that your data could go away. I think it's a remote possibility but a possibility none the less.

-Mark

 

[globus999]

"One benefit to use the AHCI drives is that it supports NCQ and if your drives do (all new drives do), you will benefit for random and multitask IO. "

Not sure if this would factor in for your particular use.

To some degree, it should. I have two raidz1, one is 4x2Tb EARS Green which will probably respond to NCQ. The other one is a mix of 1Tb and 2Tb which is less certain. However, all I have read about NCQ is that on-paper it works wonderfully. However, on real-life benchmars, is a mixed result. That's why I was asking if there is somebody here with FN and AHCI experience.

My advice is to leave it at IDE if you're happy with your system performance.

Good advice. I think I'll keep things the way they are until further notice.

Last thing, if you were to upgrade to a new version of FreeNAS, let's say Beta 5, and you lost all your data, would you be able to recover all your important data? I ask because keep in mind we are still at Beta and it is possible that your data could go away. I think it's a remote possibility but a possibility none the less.

Yes, I know. I don't have any backups and can't have them. Too much data. I know, I know, raidz1 was not designed to be a substitute for backup but I don't have much choice. I just don't have 2K to 3K of $ to invest in a decent tape unit + tapes.

I had to go with this Beta because I had other problems with 8.0, however, my policy is to always go with stable. I won't be updating until 8.0.1 prod.

 

[matthewowen01]

AHCI is 2 decades newer, use it.

 

[ProtoSD]

The thing about AHCI that I liked was the ability to power up your drives staggered, so they all don't spin up at the same time...
IF the motherboard supports it and the drives etc.

 

[joeschmuck]

I know FreeNAS does power up my drives staggered after they have spun down however when I first power on the computer all the drives start up at the same time. Wish I had AHCI on this MB I have.

 

[Brand]

I just don't have 2K to 3K of $ to invest in a decent tape unit + tapes.

You don't have to use tape as a back, especially for a home or small business server. Tape is ideal but definatly not necessary. You could use a secondary FreeNAS server or even single drives.

 

[globus999]

You don't have to use tape as a back, especially for a home or small business server. Tape is ideal but definatly not necessary. You could use a secondary FreeNAS server or even single drives.

Yes, I know, but if I would to backup to other hdd's I would need about 8 Tb worth of space. That translated into hdds (assuming I am taking a chance) with no raidz1 / mirroring would be 6x 3Tb to have two lousy full backups. That would be lot of $$$ that I don't have. Not to mention speed issues. My current peak FN8 read is about 250 Mbits/sec through CIF. Sure, I could use rsyncs which would be a tad faster, but it would still be limited by write speed which would be about 200 Mbits/second. So, 8 Tb / 200 Mb/s yields about 11 hours of spinning disks.

I am not a big fan of incremental... got a few too many restore issues with incrementals going bad.