---------- Forwarded message ----------
From: Michael Nolan <htfoot@xxxxxxxxx>
Date: Tue, Apr 10, 2012 at 9:47 PM
Subject: Re: [streaming replication] 9.1.3 streaming replication bug ?
To: Fujii Masao <masao.fujii@xxxxxxxxx>
If you're writing records with a 100MB blob object in them, you definitely need to keep more than 3 WAL segments at a time, because at 16MB each that won't hold even one of your largest records.
That's the kind of value added information that the DBA brings to the table that the database itself won't know, which is why one of the DBA's most important tasks is to properly configure the postgresql.conf file, and revise it as the database changes over time.
--
Mike Nolan
From: Michael Nolan <htfoot@xxxxxxxxx>
Date: Tue, Apr 10, 2012 at 9:47 PM
Subject: Re: [streaming replication] 9.1.3 streaming replication bug ?
To: Fujii Masao <masao.fujii@xxxxxxxxx>
On Tue, Apr 10, 2012 at 9:09 PM, Fujii Masao <masao.fujii@xxxxxxxxx> wrote:
On Wed, Apr 11, 2012 at 10:06 AM, 乔志强
> How can I do when I need a backup standby server and
> wal_keep_segments = 3 for save master disk usage(master will delete wal before send to standby now when heavy load, Need modify some config?)
Yes, increase wal_keep_segments. Even if you set wal_keep_segments to 64,
the amount of disk space for WAL files is only 1GB, so there is no need to worry
so much, I think. No?
If you're writing records with a 100MB blob object in them, you definitely need to keep more than 3 WAL segments at a time, because at 16MB each that won't hold even one of your largest records.
That's the kind of value added information that the DBA brings to the table that the database itself won't know, which is why one of the DBA's most important tasks is to properly configure the postgresql.conf file, and revise it as the database changes over time.
--
Mike Nolan
