Re: [Postgres-xc-developers] [Postgres-xc-general] IO PGXC

[Mason S. <ma...@st...>]

Sent from my IPhone

On Mar 1, 2013, at 4:13 PM, Arni Sumarlidason <Arn...@md...> wrote:

> Users,
>  
> I have 20 nodes sitting on a disk arrays, with multiple LUNs. when I issue queries – `select count(1) from table` for example, I am experiencing heavy writes and heavy reads. I expected the reads but not the writes and it has really thrown a wrench in the caching. My first assumption would be the log files, do you have any other ideas what could be causing all these writes with a select?

It could be vacuum. Also, did you just load data? Hint bits get updated, dirtying pages and causing them to be written.

>  
> Arni Sumarlidason | Software Engineer, Information Technology
> MDA | 820 West Diamond Ave | Gaithersburg, MD | USA
> O: 240-833-8200 D: 240-833-8318 M: 256-393-2803
> arn...@md...| http://www.mdaus.com 
>  
> ------------------------------------------------------------------------------
> Everyone hates slow websites. So do we.
> Make your web apps faster with AppDynamics
> Download AppDynamics Lite for free today:
> http://p.sf.net/sfu/appdyn_d2d_feb
> _______________________________________________
> Postgres-xc-general mailing list
> Pos...@li...
> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general