On Sat, Jul 18, 2009 at 11:42 AM, David Woodhouse wrote:
> On Sat, 18 Jul 2009, Dan Williams wrote:
>> I was under the impression that btrfs wanted to leverage md's stripe
>> handling logic as well, seems that is not the case?
>
> No. We do a bunch of the stuff you mention above, but entirely withi
On Sat, 18 Jul 2009, Dan Williams wrote:
On Sat, Jul 18, 2009 at 4:53 AM, David Woodhouse wrote:
On Fri, 2009-07-17 at 11:49 -0400, H. Peter Anvin wrote:
Cost, yes, of changing an on-disk format.
Personally, I don't care about that -- I'm utterly uninterested in the
legacy RAID-6 setup where
Alex Elsayed wrote:
> H. Peter Anvin wrote:
>> implementation in Java, called "Jerasure".) Implementability using real
>> array instruction sets is key to decent performance.
> Actually, it is made clear in the paper that Jerasure is written as a C
> library, and Clearsafe is the only Java impl
H. Peter Anvin wrote:
> implementation in Java, called "Jerasure".) Implementability using real
> array instruction sets is key to decent performance.
Actually, it is made clear in the paper that Jerasure is written as a C
library, and Clearsafe is the only Java implementation. Don't let the nam
On Sat, Jul 18, 2009 at 4:53 AM, David Woodhouse wrote:
> On Fri, 2009-07-17 at 11:49 -0400, H. Peter Anvin wrote:
>> Cost, yes, of changing an on-disk format.
>
> Personally, I don't care about that -- I'm utterly uninterested in the
> legacy RAID-6 setup where it pretends to be a normal disk. I t
From: Julia Lawall
If spin_lock_irqsave is called twice in a row with the same second
argument, the interrupt state at the point of the second call overwrites
the value saved by the first call. Indeed, the second call does not need
to save the interrupt state, so it is changed to a simple spin_l
David Woodhouse wrote:
I'm only interested in what we can use directly within btrfs -- and
ideally I do want something which gives me an _arbitrary_ number of
redundant blocks, rather than limiting me to 2. But the legacy code is
good enough for now¹.
When I get round to wanting more, I was thi
On 07/18/2009 07:53 AM, David Woodhouse wrote:
On Fri, 2009-07-17 at 11:49 -0400, H. Peter Anvin wrote:
Ric Wheeler wrote:
The bottom line is pretty much this: the cost of changing the encoding
would appear to outweigh the benefit. I'm not trying to claim the Linux
RAID-6 implementati
On Fri, 2009-07-17 at 11:49 -0400, H. Peter Anvin wrote:
> Ric Wheeler wrote:
> >>
> >> The bottom line is pretty much this: the cost of changing the encoding
> >> would appear to outweigh the benefit. I'm not trying to claim the Linux
> >> RAID-6 implementation is optimal, but it is simple and app
