Hm, i seem to have mixed fwrite() (which buffers data in userspace) and
write() (which apparently doesnt !)
Sorry !
> PFC <lists(at)peufeu(dot)com> writes:
>> Just a stupid question about the various fsync settings.
>> There is fsync=off, but is there fsync=fflush ?
>> fflush would mean only an OS crash could cause data loss,
>> I think.it could be useful for some applications where you need a speed
>> boost (like testing database import scripts...) without being as scary
>> as
>> fsync=off...
>
> I think you misunderstand. There aren't any scenarios where a PG crash
> (without hardware/OS crash) risks data, because we always at least
> write() data before commit. The only issue is how hard do we try to get
> the OS+hardware to push that data down to disk.
>
> regards, tom lane