Re: How do you change the size of the WAL files?

David, thanks for the response. I appreciate it. I hope the community understands the benefit of providing the functionality to be able to dynamically increase WAL size without having to re-init the cluster (which I think is the work around). In this information age an OLTP or OLAP database with an average size of 1to 3Tb size is not uncommon. With that in view an active database could generate hundreds of 16Mb files within a very short time. In my case we are moving a large active database from Oracle to Postgresql. In Postgres I am seeing an average of 15 to 23 WAL 16Mb files every minute.

Regards,
rs

-----Original Message-----
From: David Johnston [mailto:polobo(at)yahoo(dot)com]
Sent: Tuesday, January 10, 2012 9:34 AM
To: Ron Somaraju; 'Tom Lane'
Cc: 'Scott Marlowe'; pgsql-general(at)postgresql(dot)org
Subject: RE: [GENERAL] How do you change the size of the WAL files?

-----Original Message-----
From: pgsql-general-owner(at)postgresql(dot)org
[mailto:pgsql-general-owner(at)postgresql(dot)org] On Behalf Of Ron Somaraju
Sent: Monday, January 09, 2012 8:21 PM
To: Tom Lane
Cc: Scott Marlowe; pgsql-general(at)postgresql(dot)org
Subject: Re: [GENERAL] How do you change the size of the WAL files?

Once again, pros and cons should be left to users discretion because one may have latest and greatest hardware and network resources. For example a SSD on a fiber channel on a high speed network.

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And determining whether such a run-time configuration is feasible should be left to programmer's discretion since they have the best chance of knowing all the different parts of the system that relate to the feature/ability in question. You are right in that everything should be end-user configurable but maybe there are reasons that is not possible or desirable in specific situations. Regardless, the designers still have to pick reasonable defaults since the configuring 500 settings just to install the software is not realistic or desirable in its own right.

While your concerns and reasoning are well-founded currently the capability to dynamically adjust the WAL file size is not present and so the question becomes whether you can convince the community to add such functionality in a timely enough fashion or whether it is important enough to you to contract one of the service providers to research and make the necessary modifications. Simply being right doesn't mean that the current (wrong) state is going to go away - especially since it isn't broken but rather is not as flexible as it possibly could be.

David J.