Re: POC: postgres_fdw insert batching

On Fri, Jul 10, 2020 at 09:28:44AM +0500, Andrey V. Lepikhov wrote:
>On 6/28/20 8:10 PM, Tomas Vondra wrote:
>>Now, the primary reason why the performance degrades like this is that
>>while FDW has batching for SELECT queries (i.e. we read larger chunks of
>>data from the cursors), we don't have that for INSERTs (or other DML).
>>Every time you insert a row, it has to go all the way down into the
>>partition synchronously.
>
>You added new fields into the PgFdwModifyState struct. Why you didn't
>reused ResultRelInfo::ri_CopyMultiInsertBuffer field and
>CopyMultiInsertBuffer machinery as storage for incoming tuples?
>

Because I was focused on speeding-up inserts, and that is not using
CopyMultiInsertBuffer I think. I agree the way the tuples are stored
may be improved, of course.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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