Re: [HACKERS] Modeling consumed shmem sizes, and some thorns

2012-05-03 Thread Simon Riggs
On Wed, May 2, 2012 at 9:38 PM, Daniel Farina dan...@heroku.com wrote: Besides accuracy, there is a thornier problem here that has to do with hot standby (although the use case is replication more generally) when one has heterogeneously sized database resources. As-is, it is required that

Re: [HACKERS] Modeling consumed shmem sizes, and some thorns

2012-05-03 Thread Daniel Farina
On Thu, May 3, 2012 at 2:23 AM, Simon Riggs si...@2ndquadrant.com wrote: On Wed, May 2, 2012 at 9:38 PM, Daniel Farina dan...@heroku.com wrote: Besides accuracy, there is a thornier problem here that has to do with hot standby (although the use case is replication more generally) when one has

[HACKERS] Modeling consumed shmem sizes, and some thorns

2012-05-02 Thread Daniel Farina
Hello List, I'd like to share with you some experiences we've had while investigating what we'd have to do to make very-very tiny databases. First, the formulae at http://www.postgresql.org/docs/9.1/static/kernel-resources.html#SHARED-MEMORY-PARAMETERS (17-2) seem misleading, particularly with