Re: 9.6 and fsync=off

On 28 April 2016 at 22:30, David G. Johnston <david(dot)g(dot)johnston(at)gmail(dot)com>
wrote:

> On Thursday, April 28, 2016, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>
>> 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?
>>
>>
> http://www.postgresql.org/docs/current/static/runtime-config-wal.html
>
> 4th paragraph in the fsync section.
>

Thanks. I've never touched that parameter! But I could have read the docs.

--
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