Re: AW: AW: Vacuum only with 20% old tuples

Zeugswetter Andreas SB <ZeugswetterA@wien.spardat.at> writes:
>> We scan the log and come upon the rename.
>> Hmm, there's a file foo and no file bar ... looks like the 
>> rename didn't get done, so do it.  Ooops.

> No again. You come upon "starting rename operation" and then either 
>     no more log records (backend abort)
> or 
>     log record "rename succeeded"
> or
>     log record "rename failed"  --> transaction abort

> In this scenario you can decide what to do without second guessing.

If there are no more records, then you are reduced to guessing whether
you have to undo the rename or not.  If you guess wrong, you leave the
database in a corrupted state.
        regards, tom lane