RAID0 with linux mdadm

[rickbol]

I have 2 2GB SATA3 drives that I want to bundle in a RAID0 array to ~double the read\write speed for multitrack audio recording. Originally I was planning to use the onboard (fake) RAID on the mobo (Biostar TH67+), but anecdotally it appears that linux software RAID (MD) would likely perform as well, or better, and have the advantage of keeping the RAID array hardware agnostic.

The mobo provides 6 SATA ports, 2x6GB and 4x3GB as follows:

SATA 1      SATA2   (6GB)

SATA3       SATA4   (3GB)
SATA5       SATA6   (3GB)

Bozo that I am, I put the sysdrive(3GB SATA) and dvd drive on SATA1 & 2 (6GB SATA). So I only have the 3GB SATA ports left. Since my drives are 3GB SATA, would there be any advantage to spreading the drives across the SATA controller like, SATA3 & SATA5 to take advantage of processing efficiencies of hardware within the controller, or does it not really matter (just connect drives to SATA3 & SATA4, or any other combo) ?

Any other comments regarding Linux software SATA and audio tracking generally?

thx,

rickbol   

[GMaq]

Hi,

Well to be honest I'm no Linux RAID expert, as far as data transfer audio really has very modest needs, way back in the old days with IDE and ATA66 controllers I never had an issue with audio data transfers being an issue. Just having access to regular SATA operation the speeds are more than sufficient and striping type of RAID operation is certainly not required or necessary.

[rickbol]

I got this configured, and it apparently works. Documenting the steps (as best I remember) for posterity:

Most of this came rather linearly from:
  https://raid.wiki.kernel.org/
specifically:
  https://raid.wiki.kernel.org/articles/r/a/i/RAID_setup_cbb2.html

HW configuration:
2 - SATA2 disks (3GB) in RAID0, same manufacturer/model/size. Not partitioned or formatted, connected to mobo sata ports. Appear to system as /dev/sdb & /dev/sdc.

AVLinux includes the raidX kernel module drivers, so:

    modprobe raid0

then,

    cat /proc/mdstat

to verify device was created.
Also, add the kernel module to /etc/modules to load module at bootup.

    raid0

Install mdadm:

    apt-get install mdadm

apt asks about whether this raid array will host the booting system, etc. For me, no, so I don't select the options necessary for that situation.

create the raid0 array:

    mdadm --create --verbose /dev/md0 --level=stripe --raid-devices=2 /dev/sdb /dev/sdc

record the raid config into /etc/mdadm/mdadm.conf:

    mdadm --detail --scan >> /etc/mdadm/mdadm.conf

format the raid0 array (I chose standard ext4 w/defaults after consulting opensourcemusicians on irc):

    mke2fs -v -t ext4 /dev/md0

edit /etc/fstab to mount the device at bootup:

    /dev/md0   /media/data  ext4    rw,user,auto   0  2

Then, after reboot, mounting of /dev/md0 is the first message seen. /media/data is accessible for read/write. I haven't profiled performance, but it would be expected to near double from a single disk\spindle.

hope this is useful to someone sometime,

rickbol

[GMaq]

Great!

Thanks for sharing how you got it to work