Re: PG15 beta1 sort performance regression due to Generation context change

On 5/23/22 22:47, Tom Lane wrote:
> Tomas Vondra <tomas.vondra@enterprisedb.com> writes:
>> On 5/20/22 12:01, Heikki Linnakangas wrote:
>>> Could the 'context' field be moved from GenerationChunk to GenerationBlock?
> 
>> Not easily, because GetMemoryChunkContext() expects the context to be
>> stored right before the chunk. In principle we could add "get context"
>> callback to MemoryContextMethods, so that different implementations can
>> override that.
> 
> How would you know which context type to consult for that?
> 

D'oh! I knew there has to be some flaw in that idea, but I forgot about
this chicken-or-egg issue.


regards

-- 
Tomas Vondra
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