Re: Is mdextend really safe?

* Gregory Stark:

> On Unix that creates a sparse file where the intervening blocks are
> not allocated. When we later write out those blocks the filesystem
> then has to allocate space for them.

This seems to happen relatively rarely.  Creating temporary holes like
this usually results in heavily fragmented files on the file systems I
use, and I don't see this with PostgreSQL.  (It's one of my gripes
with Berkeley DB.)

However, I looked at the code recently and couldn't figure out *why*
PostgreSQL's observed behavior is this way. 8-(

--
Florian Weimer                <fweimer@bfk.de>
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