Re: [BUG 2.6.32] md/raid1: barrier disabling does not work correctlyin all cases

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OK, so I finally got back to this. Just FYI, a slight adjustment to
the patch was needed (bitmap_info now has the max_write_behind field).
It's attached. You need both the barrier-retry-fix-2 patch that I
posted a while back and this one.

Thanks,
Paul



On Tue, Feb 1, 2011 at 8:04 PM, Paul Clements w=
rote:
> On Tue, Feb 1, 2011 at 7:32 PM, NeilBrown wrote:
>> On Tue, 1 Feb 2011 15:45:16 -0500 Paul Clements om>
>> wrote:
>> Disabling behind-writes for all barrier requests would be quite easy, bu=
t it
>> might negate a lot of the value of behind writes
>
> Agreed...
>
>> I think the best option is to reject barrier writes if there are any
>> behind-write devices. =A0That would be reasonably safe and reasonably
>> consistent.
>
> Yeah, I was leaning toward this.
>
>> So maybe something like this??
>
> Yes, I think that would work.
>
> Thanks,
> Paul
>

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