On 5/02/2013 8:12 AM, Roman Mamedov wrote:

On Mon, 4 Feb 2013 20:27:42 +0000
Mathias Burén [off-list ref] wrote:

quoted

I read that the far layout gives faster read performance compared to
standard RAID1 in a 2 HDD array, so that's why I used it. I then
created yet another RAID10 f2 layout of the 3x 2 disk RAID10 volumes,
giving me /dev/md124. Filesystem doesn't matter, I need something
that's stable with good performance over the RAID set.
I just realized that out of 12 TB raw space I now only have 3TB
available, heh. So I suppose I'm going for a different layout.

Any opinions?

Hello,

Why won't you even consider RAID6? To me it seems like the perfect choice,
given the details you described (mostly reads, large files, few clients).
And the disk count is perfect, not too few and not too many, so to say :D

I was going to say the same. I run a 4 x 2Tb SATA RAID6. The read speeds 
will *easily* saturate GigE. Random seeks slow things down quite a bit - 
but you'll get that with any setup except SSD.

If its mainly sequential reads, then RAID6 will be fine.

And as I know someone will ask... Why 4 drives in RAID6? Firstly, you 
still get the redundancy of surviving 2 drive failures - but also when I 
start to run low on space I can easily add another 2Tb disk and reshape 
to 5 drives, then 6. My chassis has 8 x SATA hot swap bays - 2 x 80Gb 
RAID1 leaving the other 6 for the RAID6. By the time I fill up 6 x 2Tb 
drives, there will be other cheap multi-Tb drives to use.

-- 
Steven Haigh

Email: netwiz@crc.id.au
Web: http://www.crc.id.au
Phone: (03) 9001 6090 - 0412 935 897
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