[pgpool-committers: 7563] pgpool: Fix hang with asyncpg.

[Tatsuo Ishii]

Fix hang with asyncpg.

asyncpg (Python frontend driver with asynchronous I/O) uses extended
protocol. When it issues describe message, it is followed by Flush
message. Unfortunately Pgpool-II just buffers flush message and
frontend cannot receive the message from pgpool. To fix this, Now
SimpleForwardToFrontend() flushes the send buffer while processing
describe message.

Discussion:
https://www.pgpool.net/pipermail/pgpool-general/2021-March/007495.html

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=4cd9f4a38c004851630e32011521c49c90be3b9c

Modified Files
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src/protocol/pool_process_query.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)