Re: Piggybacking vacuum I/O

I'd like to see still more evidence that it's a problem before we start
changing that piece of code. It has served us well for years.

Bruce Momjian wrote:
> Is there a TODO here?
>
> ---------------------------------------------------------------------------
>
> Heikki Linnakangas wrote:
>> Pavan Deolasee wrote:
>>> Another simpler solution for VACUUM would be to read the entire CLOG file
>>> in local memory. Most of the transaction status queries can be satisfied
>>> from
>>> this local copy and the normal CLOG is consulted only when the status is
>>> unknown (TRANSACTION_STATUS_IN_PROGRESS)
>> The clog is only for finished (committed/aborted/crashed) transactions.
>> If a transaction is in progress, the clog is never consulted. Anyway,
>> that'd only be reasonable for vacuums, and I'm actually more worried if
>> we had normal backends thrashing the clog buffers.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com