Re: Summary and Plan for Hot Standby

Simon Riggs wrote:
> On Sun, 2009-11-15 at 16:07 +0200, Heikki Linnakangas wrote:
> 
>> The assumption that b-tree vacuum records don't need conflict
>> resolution because we did that with the additional cleanup-info record
>> works ATM, but it hinges on the fact that we don't delete any tuples
>> marked as killed while we do the vacuum. 
> 
>> That seems like a low-hanging
>> fruit that I'd actually like to do now that I spotted it, but will
>> then need to fix b-tree vacuum records accordingly. We'd probably need
>> to do something about the previous item first to keep performance
>> acceptable.
> 
> We can optimise that by using the xlog pointer of the HeapInfo record.
> Any blocks cleaned that haven't been further updated can avoid
> generating further btree deletion records.

Sorry, I don't understand that. (Remember that marking index tuples as
killed is not WAL-logged.)

> You spotted this issue only this morning??

Yesterday evening.

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