Horton

Re: [EXTERNAL] Re: Support load balancing in libpq

Andrey Borodin <amborodin86@gmail.com>

View thread View on postgr.es
From: Andrey Borodin <amborodin86@gmail.com>
To: Jelte Fennema <postgres@jeltef.nl>
Cc: Greg S <stark.cfm@gmail.com>, Jacob Champion <jchampion@timescale.com>, Maxim Orlov <orlovmg@gmail.com>, Jelte Fennema <Jelte.Fennema@microsoft.com>, Michael Banck <mbanck@gmx.net>, Aleksander Alekseev <aleksander@timescale.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>, Andres Freund <andres@anarazel.de>
Date: 2023-03-03T04:52:49Z
Lists: pgsql-hackers 
On Wed, Mar 1, 2023 at 12:03 PM Jelte Fennema <postgres@jeltef.nl> wrote:
>
> done and updated cf entry
>

Hi Jelte!

I've looked into the patch. Although so many improvements can be
suggested, It definitely makes sense as-is too.
These improvements might be, for example, sorting hosts according to
ping latency or something like that. Or, perhaps, some other balancing
policies. Anyway, randomizing is a good start too.

I want to note that the Fisher-Yates algorithm is implemented in a
difficult to understand manner.
+if (j < i) /* avoid fetching undefined data if j=i */
This stuff does not make sense in case of shuffling arrays inplace. It
is important only for making a new copy of an array and only in
languages that cannot access uninitialized values. I'd suggest just
removing this line (in both cases).


Best regards, Andrey Borodin.

Commits

  1. Fix pointer cast for seed calculation on 32-bit systems

  2. Copy and store addrinfo in libpq-owned private memory

  3. libpq: Use modern socket flags, if available.