Re: [gentoo-amd64] Is my RAID performance bad possibly due to starting sector value?

[Mark Knecht <markknecht@gmail.com>]

On Mon, Jun 24, 2013 at 11:47 AM, Volker Armin Hemmann
<volkerarmin@googlemail.com> wrote:
> Am 20.06.2013 22:45, schrieb Mark Knecht:
>> On Thu, Jun 20, 2013 at 12:16 PM, Volker Armin Hemmann
>> <volkerarmin@googlemail.com> wrote:
>> <SNIP>
>>> man mkfs.xfs
>>>
>>> man mkfs.ext4
>>>
>>> look for stripe size etc.
>>>
>>> Have fun.
>>>
>> Volker,
>>    I find way down at the bottom of the RAID setup page that they do
>> say stride & stripe are important for RAID4 & RAID5, but remain
>> non-committal for RAID6.
>
> raid 6 is just raid5 with additional parity. So stripe size is not less
> important.
>

Yeah, as I continued to study that became more apparent. The Linux
RAID wiki not saying about it was (apparently) just an oversight on
their part.

At this point I'm basically getting set up to tear my whole machine
apart and rebuild it from scratch. When I do I'm benchmark whatever
RAID options I think will meet my long term needs and then report back
anything I find.

Personally, I think that RAID6 should be just slightly slower than
RAID5, and use slightly more CPU power doing it. How RAID5/6 really
compare with RAID1 isn't really that much of an issue for me as using
only RAID1 won't give me enough storage using any combinations of my 5
500GB drives.

I think if I was into spending some money I'd look at buying a second
SSD and do RAID1 for my / and then just use the disks for the VMs &
video, but don't see that as an option right now.

Cheers,
Mark