From: Colin Walters Date: Tue, 19 Jul 2016 14:24:18 +0000 (-0400) Subject: docs/formats: Elaborate a bit on delta from NULL usage X-Git-Tag: archive/raspbian/2022.1-3+rpi1~1^2~4^2~49^2~65 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=d49d42b983483f990460f64af59b7d6b9266f058;p=ostree.git docs/formats: Elaborate a bit on delta from NULL usage See discussion on ostree-list. Closes: #402 Approved by: gatispaeglis --- diff --git a/docs/manual/formats.md b/docs/manual/formats.md index 87d0005f..e3fe00e1 100644 --- a/docs/manual/formats.md +++ b/docs/manual/formats.md @@ -79,7 +79,10 @@ concept of a "static delta". These deltas are targeted to be a delta between two specific commit objects, including "bsdiff" and "rsync-style" deltas within a content object. Static deltas also support `from NULL`, where the client can -more efficiently download a commit object from scratch. +more efficiently download a commit object from scratch - this is +mostly useful when using OSTree for containers, rather than OS images. +For OS images, one tends to download an installer ISO or qcow2 image +which is a single file that contains the tree data already. Effectively, we're spending server-side storage (and one-time compute cost), and gaining efficiency in client network bandwidth.