On 2/9/21 9:35 AM, tsunakawa.ta...@fujitsu.com wrote:
From: tsunakawa.ta...@fujitsu.com <tsunakawa.ta...@fujitsu.com>
From: Andrey Lepikhov <a.lepik...@postgrespro.ru>
Also, I might defer working on the extended part (v9 0003 and 0004) and further
separate them in a different thread, if it seems to take longer.
I reviewed them but haven't rebased them (it seems to take more labor.)
Andrey-san, could you tell us:
* Why is a separate FDW connection established for each COPY? To avoid using
the same FDW connection for multiple foreign table partitions in a single COPY
run?
With separate connection you can init a 'COPY FROM' session for each
foreign partition just one time on partition initialization.
* In what kind of test did you get 2-4x performance gain? COPY into many
foreign table partitions where the input rows are ordered randomly enough that
many rows don't accumulate in the COPY buffer?
I used 'INSERT INTO .. SELECT * FROM generate_series(1, N)' to generate
test data and HASH partitioning to avoid skews.
--
regards,
Andrey Lepikhov
Postgres Professional
