[dm-devel] dm-crypt barrier support is effective

[Jon Nelson]

On Wed, Dec 1, 2010 at 12:24 PM, Milan Broz <mbroz at redhat.com> wrote:
> On 12/01/2010 06:35 PM, Matt wrote:
>> Thanks for pointing to v6 ! I hadn't noticed that there was a new one :)
>>
>> Well, so I'll restore my box to a working/productive state and will
>> try out v6 (I'm pretty confident that it'll work without problems).
>
> It's the same as previous, just with fixed header (to track it properly
> in patchwork) , second patch adds some read optimisation, nothing what
> should help here.
>
> Anyway, I run several tests on 2.6.37-rc3+ and see no integrity
> problems (using xfs,ext3 and ext4 over dmcrypt).
>
> So please try to check which change causes these problems for you,
> it can be something completely unrelated to these patches.
>
> (If if anyone know how to trigger some corruption with btrfs/dmcrypt,
> let me know I am not able to reproduce it either.)

Perhaps this is useful: for myself, I found that when I started using
2.6.37rc3 that postgresql starting having a *lot* of problems with
corruption. Specifically, I noted zeroed pages, corruption in headers,
all sorts of stuff on /newly created/ tables, especially during index
creation. I had a fairly high hit rate of failure. I backed off to
2.6.34.7 and have *zero* problems (in fact, prior to 2.6.37rc3, I had
never had a corruption issue with postgresql). I ran on 2.6.36 for a
few weeks as well, without issue.

I am using kcrypt with lvm on top of that, and ext4 on top of that.

-- 
Jon