[pgpool-committers: 8075] pgpool: Fix connection counter issue when reserved_connections is 0.

[Tatsuo Ishii]

Fix connection counter issue when reserved_connections is 0.

If reserved_connections is 0, we don't need to manage the connection
counter to check if the count is larger than
(pool_config->num_init_children - pool_config->reserved_connections).
So remove the check.  This will prevent unwanted "Sorry, too many
clients already" error" by accidental counter leak.

For reserved_connections > 0 case, we need to fix the counter leak but
it's another story.

Discussion: https://www.pgpool.net/pipermail/pgpool-general/2021-October/007808.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=acd400b6ca4814cd7d078883e9f7a9964f9f26d9

Modified Files
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src/protocol/child.c | 40 ++++++++++++++++++++++------------------
1 file changed, 22 insertions(+), 18 deletions(-)