Re: Documentation Update: Document pg_start_backup checkpoint behavior

Bruce Momjian <bruce(at)momjian(dot)us> writes:
> Tom Lane wrote:
>> Still, I don't much like this solution. I agree with Heikki:
>> let's just fix it.

> Agreed, fixing it is better than trying to document/report odd behavior.

> There was talk about making pg_start_backup do an immediate checkpoint
> but there was some discussion that you wouldn't want an I/O storm from
> pg_start_backup(). However, figuring you are going to do the tar backup
> anyway, the pg_start_backup I/O seems trivial.

The solution Heikki is proposing is to let the user choose immediate
or slow checkpoint. I agree that there's not much point in the latter
if you are using something dumb like tar to take the filesystem backup,
but maybe the user has something smarter that won't cause such a big
I/O storm.

regards, tom lane