ORDER BY too slow in Foreign Table using postgres_fdw

Hi all,

On PostgreSQL *v.9.6, *when using *postgres_fdw*, I got an issue with "*ORDER
BY*" (here's my question on stackexchange
<https://dba.stackexchange.com/questions/179744/order-by-too-slow-in-foreign-table-using-postgres-fdw>
).

*Query on Foreign Table*

SELECT id, info
FROM user_info
WHERE info ->> 'key1'= '1'
ORDER BY id
LIMIT 10;

Limit (cost=10750829.63..10750829.65 rows=10 width=40) (actual
time=550059.320..550059.326 rows=10 loops=1)
-> Sort (cost=10750829.63..10751772.77 rows=377257 width=40) (actual
time=550059.318..550059.321 rows=10 loops=1)
Sort Key: id
Sort Method: top-N heapsort Memory: 26kB
-> Foreign Scan on user_info (cost=100.00..10742677.24
rows=377257 width=40) (actual time=1.413..536718.366 rows=68281020 loops=1)
Filter: ((info ->> 'key1'::text) = '1'::text)
Rows Removed by Filter: 7170443
Planning time: 4.097 ms
*Execution time: 550059.597 ms*

*Query on remote server*

EXPLAIN ANALYSE
SELECT id, info
FROM user_info_raw
WHERE info ->> 'key1'= '1'
ORDER BY id
LIMIT 10;

Limit (cost=0.57..1296.95 rows=10 width=59) (actual time=0.043..0.073
rows=10 loops=1)
-> Index Scan using idx_user_info_raw_info on user_info_raw
(cost=0.57..68882850.88 rows=531346 width=59) (actual time=0.042..0.070
rows=10 loops=1)
Filter: ((info ->> 'key1'::text) = '1'::text)
Planning time: 0.192 ms
* Execution time: 0.102 ms *

Please help me to figure out the solution for that issue .

Thank you