Re: data_checksums enabled by default (was: Move --data-checksums to common options in initdb --help)

On Fri, Jan  8, 2021 at 09:46:58AM -0500, David Steele wrote:
> On 1/8/21 5:03 AM, Andres Freund wrote:
> > On Fri, Jan 8, 2021, at 01:53, Laurenz Albe wrote:
> > > 
> > > The serious crowd are more likely to choose a non-default setting
> > > to avoid paying the price for a feature that they don't need.
> > 
> > I don't really buy this argument. That way we're going to have an ever growing set of things that need to be tuned to have a database that's usable in an even halfway busy setup. That's unavoidable in some cases, but it's a significant cost across use cases.
> > 
> > Increasing the overhead in the default config from one version to the next isn't great - it makes people more hesitant to upgrade. It's also not a cost you're going to find all that quickly, and it's a really hard to pin down cost.
> 
> I'm +1 for enabling checksums by default, even with the performance
> penalties.
> 
> As far as people upgrading, one advantage is existing pg_upgrade'd databases
> would not be affected. Only newly init'd clusters would get this setting.

I think once we have better online enabling of checksums people can more
easily test the overhead on their workloads.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee