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From: Zsolt Parragi <zsolt.parragi@percona.com>
Date: Tue, 12 May 2026 22:05:45 +0100
Message-ID: 
 <CAN4CZFOjC2GA55t075OzWZYbRmTt6+bWrLA0=sM_tuQUW9A2_A@mail.gmail.com>
Subject: Re: Feature: Use DNS SRV records for connecting
To: Andrey Borodin <x4mmm@yandex-team.ru>
Cc: Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>,
	Feike Steenbergen <feikesteenbergen@gmail.com>,
	PostgreSQL mailing lists <pgsql-hackers@postgresql.org>
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Hello!

Shouldn't srvhost be freed in freePGconn?

+ /*
+ * If srvhost is set, validate mutual exclusivity with host/hostaddr and
+ * then resolve _postgresql._tcp.<srvhost> SRV records, populating
+ * conn->pghost and conn->pgport from the sorted results.  This must
+ * happen before the host-array allocation below.
+ */
+ if (conn->srvhost != NULL && conn->srvhost[0] != '\0')

Shouldn't this also cover port? The current behavior with it seems inconsistent.

> The resolved host list is sorted per RFC 2782 and injected into the
> existing multi-host machinery before connhost[] is built, so
> target_session_attrs, load_balance_hosts, and failover work on the
> expanded list without any changes to PQconnectPoll.

Doesn't RFC 2782 specifies a weighted random selection? The current
code seems to be deterministically sorted by weight.
RFC also says that weight=0 should be specially handled, it provides a
detailed algorithm about the random selection method.