Merge pull request #925 from integer32llc/snapshot-announcement

Announcement that the snapshot branches are moving

Author: Mark-Simulacrum

posts/2022-02-14-crates-io-snapshot-branches.md

@@ -0,0 +1,42 @@
+---
+layout: post
+title: "Crates.io Index Snapshot Branches Moving"
+author: The Crates.io Team
+release: false
+---
+
+Every so often, the [crates.io index](https://github.com/rust-lang/crates.io-index)'s Git history
+is [squashed into one
+commit](https://internals.rust-lang.org/t/cargos-crate-index-upcoming-squash-into-one-commit/8440)
+to minimize the history Cargo needs to download. When the index is squashed, we save snapshots
+to preserve the history of crate publishes.
+
+Currently, those snapshots are stored as branches in the main index Git repository. Those branches
+are using server resources though, as the server still has to consider their contents whenever
+Cargo asks for the master branch. We will be deleting the snapshot branches from this repository to
+ensure that all objects referenced in the master branch will only be compressed against other
+objects in the master branch, ensuring that the current clone behavior will be much more efficient
+on the server side.
+
+Here's how this might affect you:
+
+## If you use Cargo
+
+You should not see any effects from this change. Cargo does not use the snapshot branches, and
+Cargo regularly handles index squashes. If you do see any issues, they are a bug, please [report
+them on the Cargo repo](https://github.com/rust-lang/cargo).
+
+## If you use the snapshot branches
+
+In one week, on 2022-02-21, we will be removing all snapshot branches from the crates.io-index
+repo. All snapshot branches, both historical and in the future, are and will be in the
+[rust-lang/crates.io-index-archive repo](https://github.com/rust-lang/crates.io-index-archive)
+instead. Please update any scripts or tools referencing the snapshot branches by that time.
+
+## In the future
+
+In the medium term, we're working to prioritize the completion of [in-progress
+work](https://github.com/rust-lang/cargo/issues/9069) to add a way to serve the index as static
+files on HTTP, which will further ease the server load. The index repository will *not* be going
+away so that older versions of Cargo will continue to work. See [RFC
+2789](https://github.com/rust-lang/rfcs/pull/2789) for more details.