Re: Built-in connection pooler

On Thu, 15 Aug 2019 at 06:01, Konstantin Knizhnik
<k.knizhnik@postgrespro.ru> wrote:
>
> I have implemented one more trick reducing number of tainted backends:
> now it is possible to use session variables in pooled backends.
>
> How it works?
> Proxy determines "SET var=" statements and  converts them to "SET LOCAL
> var=".
> Also all such assignments are concatenated and stored in session context
> at proxy.
> Then proxy injects this statement inside each transaction block or
> prepend to standalone statements.
>
> This mechanism works only for GUCs set outside transaction.
> By default it is switched off. To enable it you should switch on
> "proxying_gucs" parameter.
>
>

there is definitively something odd here. i applied the patch and
changed these parameters

connection_proxies = '3'
session_pool_size = '33'
port = '5433'
proxy_port = '5432'

after this i run "make installcheck", the idea is to prove if an
application going through proxy will behave sanely. As far as i
understood in case the backend needs session mode it will taint the
backend otherwise it will act as transaction mode.

Sadly i got a lot of FAILED tests, i'm attaching the diffs on
regression with installcheck and installcheck-parallel.
btw, after make installcheck-parallel i wanted to do a new test but
wasn't able to drop regression database because there is still a
subscription, so i tried to drop it and got a core file (i was
connected trough the pool_worker), i'm attaching the backtrace of the
crash too.

-- 
Jaime Casanova                      www.2ndQuadrant.com
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