Re: WIP checksums patch - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: WIP checksums patch
Date
Msg-id 20121001144300.GA30089@momjian.us
Whole thread Raw
In response to Re: WIP checksums patch  (Jeff Davis <pgsql@j-davis.com>)
Responses Re: WIP checksums patch  (Jeff Davis <pgsql@j-davis.com>)
List pgsql-hackers
On Sun, Sep 30, 2012 at 07:09:20PM -0700, Jeff Davis wrote:
> On Fri, 2012-09-14 at 17:58 -0700, Jeff Davis wrote:
> > This is just a rebased version of the patch by Simon here:
> 
> I just noticed the following note in the docs for this patch:
> 
>   The default is <literal>off</> for backwards compatibility and
>   to allow upgrade. The recommended setting is <literal>on</> though
>   this should not be enabled until upgrade is successfully complete
>   with full set of new backups.
> 
> I don't understand what that means -- if they have the page_checksums
> GUC available, then surely upgrade is complete, right? And what is the
> backwards-compatibility issue?
> 
> Also, it looks out of date, because the default in guc.c is set to true.
> I think we should probably default to true, because it's safer and it
> can always be disabled at runtime, but I don't have a strong opinion
> about that.

I think this need to clearly state "pg_upgrade", not a dump/restore
upgrade, which would be fine.  It would be interesting to have
pg_upgrade change this setting, or tell the user to change it.  I am not
sure enough people are using pg_upgrade to change a default value.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +



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