Re: silent data loss with ext4 / all current versions

On 02/04/2016 09:59 AM, Michael Paquier wrote:
> On Tue, Feb 2, 2016 at 9:59 AM, Andres Freund <andres@anarazel.de> wrote:
>> On 2016-02-02 09:56:40 +0900, Michael Paquier wrote:
>>> And there is no actual risk of data loss
>>
>> Huh?
>
> More precise: what I mean here is that should an OS crash or a power
> failure happen, we would fall back to recovery at next restart, so we
> would not actually *lose* data.

Except that we actually can't perform the recovery properly because we 
may not have the last WAL segment (or multiple segments), so we can't 
replay the last batch of transactions. And we don't even notice that.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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