Hi,

On 2021-01-12 13:14:45 -0800, Darrick J. Wong wrote:

ALLOCSP64 can only allocate pre-zeroed blocks as part of extending EOF,
whereas a new FZERO flag means that we can pre-zero an arbitrary range
of bytes in a file.  I don't know if Avi or Andres' usecases demand that
kind of flexibilty but I know I'd rather go for the more powerful
interface.

Postgres/I don't at the moment have a need to allocate "written" zeroed
space anywhere but EOF. I can see some potential uses for more flexible
pre-zeroing in the future though, but not very near term.

Greetings,

Andres Freund