Re: Reviewers Guide to Deferred Transactions/TransactionGuarantee

On Thu, 2007-04-05 at 22:56 +0100, Simon Riggs wrote:
> transaction_guarantee.v11.patch

correct files attached

> Open Questions
> --------------
>
> 1. Should the DFC use a standard hash table? Custom code allows both
> additional speed and the ability to signal when it fills.
>
> 2. Should tqual.c update the LSN of a heap page with the LSN of the
> transaction commit that it can read from the DF cache?

I now think we should update the LSN of the page, but not changed yet.

> 3. Should the WALWriter also do the wal_buffers half-full write at the
> start of XLogInsert() ?

Not that important

> 4. The recent changes to remove CheckpointStartLock haven't changed the
> code path for deferred transactions, so a similar solution might be
> possible there also.

Some further discussion required here, I think. That change may actually
have introduced a slight risk into the patch. Will raise at review.

> 5. Is it correct to do WAL-before-flush for clog only, or should this
> be multixact also?

Not necessary

--
Simon Riggs
EnterpriseDB http://www.enterprisedb.com