Re: fsync-pgdata-on-recovery tries to write to more files than previously

On Mon, May 25, 2015 at 9:54 PM, Stephen Frost <sfrost(at)snowman(dot)net> wrote:
> I certainly see your point, but Tom also pointed out that it's not great
> to ignore failures during this phase:
>
> * Tom Lane (tgl(at)sss(dot)pgh(dot)pa(dot)us) wrote:
>> Greg Stark <stark(at)mit(dot)edu> writes:
>> > What exactly is failing?
>> > Is it that fsync is returning -1 ?
>> According to the original report from Christoph Berg, it was open()
>> not fsync() that was failing, at least in permissions-based cases.
>>
>> I'm not sure if we should just uniformly ignore all failures in this
>> phase. That would have the merit of clearly not creating any new
>> startup failure cases compared to the previous code, but as you say
>> sometimes it might mean ignoring real problems.
>
> If we accept this, then we still have to have the lists, to decide what
> to fail on and what to ignore. If we're going to have said lists tho, I
> don't really see the point in fsync'ing things we're pretty confident
> aren't ours.

No, that's not right at all. The idea, at least as I understand it,
would be decide which errors to ignore by looking at the error code,
not by looking at which file is involved.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company