RE: [HACKERS] Vacuum analyze bug CAUGHT

Hi

Vacuum couldn't preserve consistency without locking.
I'm anxious about locking for system tables.

>
> Hi
>
> Okee, I have caught the vacuum analyse crash that was giving me a load of
> grief
>

[snip]

>
> Then, in psql, I run and get the following result:
>
> -----------
>
> crashtest=> vacuum analyze;
> NOTICE: Rel pg_type: TID 4/3: InsertTransactionInProgress 129915
> - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/5: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/6: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/7: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/8: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/9: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/10: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/11: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_attribute: TID 23/12: InsertTransactionInProgress
> 129915 - can't shrink relation
> NOTICE: Rel pg_class: TID 3/22: InsertTransactionInProgress
> 129915 - can't shrink relation

CREATE TABLE doesn't lock system tables till end of transaction.
It's a cause of these NOTICE messages.

Should we lock system tables till end of transaction ?

Moreover CREATE TABLE doesn't acquire any lock for pg_attribute
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
while tuples are inserted into pg_attribute.
Concurrent vacuum may corrupt pg_attribute.

Regards.

Hiroshi Inoue
Inoue(at)tpf(dot)co(dot)jp