Re: Idea: recycle WAL segments, don't delete/recreate 'em

tgl wrote:

: [...]  (We have to physically fill each segment with zeroes to
: ensure that the system has actually allocated a whole 16MB to it;
: otherwise we fall victim to the "hole-saving" allocation technique
: of most Unix filesystems.)  [...]

Could you explain how postgresql can "fall victim" the filesystem hole
mechanism?  Just hoping to force actual storage allocation, or hoping
to discourage fragmentation?

- FChE