Обсуждение: pgsql: Revert "Cannot use WL_SOCKET_WRITEABLE without WL_SOCKET_READABL

Revert "Cannot use WL_SOCKET_WRITEABLE without WL_SOCKET_READABLE."

This reverts commit 3a9e64aa0d96c8ffb6c682b082d0f72b1d373327.

Commit 4bad60e3 fixed the root of the problem that 3a9e64aa worked
around.

This enables proper pipelining of commands after terminating
replication, eliminating an undocumented limitation.

Discussion: https://postgr.es/m/3d57bc29-4459-578b-79cb-7641baf53c57%40iki.fi
Backpatch-through: 9.5

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/fde5f130c9c30e75c7a8ee33095a6a7e79d5b626

Modified Files
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src/backend/replication/walsender.c | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)