To: pgsql-admin@postgresql.org
From: Thomas Kellerer <spam_eater@gmx.net>
Subject: Re: High Availability: Hot Standby vs. Warm Standby
Date: Fri, 09 Jul 2010 18:31:56 +0200
Lines: 28
Message-ID: <i17itq$g11$1@dough.gmane.org>
References: <i172f8$kug$1@dough.gmane.org>
	<AANLkTilFPekuBaypffaEgBxjreDdusVhqz0mSE_paJ8g@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; de;
	rv:1.8.1.21) Gecko/20090302 Thunderbird/2.0.0.21 Mnenhy/0.7.5.666
In-Reply-To: <AANLkTilFPekuBaypffaEgBxjreDdusVhqz0mSE_paJ8g@mail.gmail.com>

Hi,

Rob Wultsch wrote on 09.07.2010 18:14:
>> I am aware that I can use the 9.0 standby server for read only queries, but
>> that is (currently) not something we need
>>
>
> Taking SQL backups without impacting the master might be something to consider.

Interesting point. Thanks for mentioning that.

  
>> I'm wondering about the differences when the failover situation occurs. From
>> reading the docs, I get the impression that 9.0's streaming replication
>> might be faster than 8.4's WAL shipping, but otherwise offers the same level
>> of data protection.
>>
>> Is there a difference in how much data could potentially be lost in case of
>> a failover?
>
> 9.0 has streaming replication so much less data would likely be lost.
> WAL logs are generally 16 MB and often shipped when completed.

So my assumption is correct that streaming replication does mean that in case of a failover less transactions are lost?
  

Regards
Thomas