Message-ID: <1512994403.12727.23.camel@redhat.com>
Subject: Re: Prepared Transactions
From: jwhiting@redhat.com
To: Riaan Stander <rstander@exa.co.za>
Cc: pgsql-performance@lists.postgresql.org, Sergei Kornilov <sk@zsrv.org>
Date: Mon, 11 Dec 2017 12:13:23 +0000
In-Reply-To: <96631512980099@web21g.yandex.ru>
References: <160430354e0.27df.e05fafc80f8daf1488764675043d44fb@exa.co.za>
	 <96631512980099@web21g.yandex.ru>
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Hi Riaan,
 You benefit from greater fault tolerance performance. Recovering from
a crash/network outage is quicker/easier.
 On the downside you might see a reduction in transactions per second.

 It's worth benchmarking. To see if the impact to tps is acceptable to
live with.

Jeremy

On Mon, 2017-12-11 at 11:14 +0300, Sergei Kornilov wrote:
> Hello!
> 
> You need prepared transactions only if you need two-phase commit to
> provide distributed atomic transaction on multiple different
> databases.
> If you not need distributed transactions - you not needed prepared
> transactions at all.
> But if you need distributed transactions - here is no more choice
> regardless performance questions.
> 
> As say in documentation https://www.postgresql.org/docs/current/stati
> c/sql-prepare-transaction.html
> > Unless you're writing a transaction manager, you probably shouldn't
> > be using PREPARE TRANSACTION.
> 
> Regards, Sergei
>