Re: DB on mSATA SSD

Hi,


On 04/23/15 14:33, John McKown wrote:
>
> ​That's a really old release. But I finally found some doc on it. And
> 8.4 does appear to have TABLESPACEs in it.
>
> http://www.postgresql.org/docs/8.4/static/manage-ag-tablespaces.html
>
> <quote>
>
> To define a tablespace, use the CREATE TABLESPACE
> <http://www.postgresql.org/docs/8.4/static/sql-createtablespace.html> command,
> for example::
>
> CREATE TABLESPACE fastspace LOCATION '/mnt/sda1/postgresql/data';
>
> The location must be an existing, empty directory that is owned by the
> PostgreSQL system user. All objects subsequently created within the
> tablespace will be stored in files underneath this directory.

I think you should read this:

http://thebuild.com/blog/2013/03/10/you-cannot-recover-from-the-loss-of-a-tablespace/

in other words, using tablespaces for placing some of the data into a
RAM filesystem (which may disappear) is a rather terrible idea. In case
of crash you won't be able to even start the database, because it will
try to recover the tablespace.


--
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services