Re: 9.6 and fsync=off

On 27 April 2016 at 17:04, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:

> On 27 April 2016 at 21:44, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> Petr Jelinek <petr(at)2ndquadrant(dot)com> writes:
>> > +1 (Abhijit's wording with data loss changed to data corruption)
>>
>> I'd suggest something like
>>
>> #fsync = on # flush data to disk for crash
>> safety
>> # (turning this off can cause
>> # unrecoverable data corruption!)
>>
>>
> Looks good.
>
> The docs on fsync are already good, it's just a matter of making people
> think twice and actually look at them.
>

If fsync=off and you turn it on, does it fsync anything at that point?

Or does it mean only that future fsyncs will occur?

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