On 2019-07-19 10:41:31 -0400, Matthew Pounsett wrote:
> Okay. So I guess the short answer is no, nobody really knows how to
> judge how much space is required for an upgrade? :)
As I understand it, a pg_upgrade --link uses only negligible extra
space. It duplicates a bit of householding information, but not your
data tables or indexes. Your 18 TB table will definitely not be duplicated
during the upgrade if you can use --link.
hp
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