Subject: Re: Built-in connection pooler
To: Zhihong Yu <zyu@yugabyte.com>
Cc: Daniel Gustafsson <daniel@yesql.se>,
 Konstantin Knizhnik <k.knizhnik@postgrespro.ru>,
 Michael Paquier <michael@paquier.xyz>, David Steele <david@pgmasters.net>,
 "ideriha.takeshi@fujitsu.com" <ideriha.takeshi@fujitsu.com>,
 Jaime Casanova <jaime.casanova@2ndquadrant.com>,
 Tomas Vondra <tomas.vondra@2ndquadrant.com>,
 Ryan Lambert <ryan@rustprooflabs.com>, Thomas Munro
 <thomas.munro@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
 Bruce Momjian <bruce@momjian.us>, Dimitri Fontaine <dim@tapoueh.org>,
 Alvaro Herrera <alvherre@2ndquadrant.com>
References: 
 <OSAPR01MB1985068ABB08A85828999460EA770@OSAPR01MB1985.jpnprd01.prod.outlook.com>
 <a79b0687-c94d-8e0e-835b-85782c7b68ec@postgrespro.ru>
 <OSAPR01MB1985554A600901FF0B8D125FEA710@OSAPR01MB1985.jpnprd01.prod.outlook.com>
 <b5ff3ff2-b75c-c518-f75e-a472fa5292cc@postgrespro.ru>
 <3edbc4d2-ebe8-d73f-a3f4-e043bc504f17@pgmasters.net>
 <ad6a2c97-2410-1778-fade-20502368fcbb@postgrespro.ru>
 <F56E550A-62C4-4F72-B763-A0496DF23B3D@yesql.se>
 <f16e8099-75ab-ea23-8678-0b78ca25a2d0@postgrespro.ru>
 <A6A82977-D032-4DA4-885A-BE993F6F45C3@yesql.se>
 <e42c8d25-9a1c-a835-c422-0dc56e5775a6@postgrespro.ru>
 <20200917050711.GK2873@paquier.xyz>
 <0fd2ee44-e75b-8d14-4192-641aa07d6c89@postgrespro.ru>
 <FB6148A2-3BE2-4860-B4B8-5726ED1EBB42@yesql.se>
 <f2d9757e-e78f-fa44-a8fe-b85a06c74326@garret.ru>
 <CALNJ-vSnRHYi2q5S7pA39eXNccba0Qk9DhL2J9_C-j1TC5TE3Q@mail.gmail.com>
From: Konstantin Knizhnik <knizhnik@garret.ru>
Message-ID: <0d9c9165-3389-dd70-3429-df2facce44ec@garret.ru>
Date: Mon, 22 Mar 2021 12:05:53 +0300
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Hi,
Thank you for review!

On 21.03.2021 23:59, Zhihong Yu wrote:
> Hi,
>
> +          With <literal>load-balancing</literal> policy postmaster 
> choose proxy with lowest load average.
> +          Load average of proxy is estimated by number of clients 
> connection assigned to this proxy with extra weight for SSL connections.
>
> I think 'load-balanced' may be better than 'load-balancing'.

Sorry, I am not a native speaker.
But it seems to me (based on the articles I have read), then 
"load-balancing" is more widely used term:

https://en.wikipedia.org/wiki/Load_balancing_(computing)

> postmaster choose proxy -> postmaster chooses proxy

Fixed.

>
> +          Load average of proxy is estimated by number of clients 
> connection assigned to this proxy with extra weight for SSL connections.
>
> I wonder if there would be a mixture of connections with and without SSL.
Why not? And what is wrong with it?

>
> +         Terminate an idle connection pool worker after the specified 
> number of milliseconds.
>
> Should the time unit be seconds ? It seems a worker would exist for at 
> least a second.
>
Most of other similar timeouts: statement timeout, session timeout... 
are specified in milliseconds.

> + * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
>
> It would be better to update the year in the header.

Fixed.

>
> +        * Use then for launching pooler worker backends and report error
>
> Not sure I understand the above sentence. Did you mean 'them' instead 
> of 'then' ?

Sorry, it is really mistyping.
"them" should be used.
Fixed.