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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