Re: GIN fast update technique and work_mem

On 2013-10-24 18:40:46 +0900, Amit Langote wrote:
> While going through the documentation for GIN fast update technique, I read -
>
> "...or if the pending list becomes too large (larger than work_mem),
> the entries are moved to the main GIN data structure using the same
> bulk insert techniques used during initial index creation."
>
> The "work_mem" links to work_mem setting documentation.
>
> Whereas in the src/backend/access/gin/README, as one of the features
> of GIN, I read -
>
> "...* Optimized index creation (Makes use of maintenance_work_mem to accumulate
> postings in memory.)"
>
> So, which one is it - work_mem or maintenance_work_mem?
>
> Or are these things unrelated?

Yes. One is about the initial index creation, the other about insertions
into an existing index.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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