persistent-nodemap: write down the sprint conclusion
This write down the plan for turning feature that are only fast when the rust
extension exists. Future changesets will implement it.
Differential Revision: https://phab.mercurial-scm.org/D9754
--- a/mercurial/configitems.py Thu Jan 14 00:33:40 2021 +0100
+++ b/mercurial/configitems.py Thu Jan 14 00:37:36 2021 +0100
@@ -1266,9 +1266,21 @@
b'usestore',
default=True,
)
-# Right now, the only efficient implement of the nodemap logic is in Rust, so
-# the persistent nodemap feature needs to stay experimental as long as the Rust
-# extensions are an experimental feature.
+# Right now, the only efficient implement of the nodemap logic is in Rust,
+#
+# The case was discussed that the 5.6 sprint and the following was decided for
+# feature that have an optional fast implementation (and are a performance
+# regression in the others)
+#
+# * If the fast implementation is not available, Mercurial will refuse to
+# access repository that requires it. Pointing to proper documentation
+#
+# * An option exist to lift that limitation and allow repository access.
+#
+# Such access will emit a warning unless configured not to.
+#
+# * When sufficiently mature, the feature can be enabled by default only for
+# installation that supports it.
coreconfigitem(
b'format', b'use-persistent-nodemap', default=False, experimental=True
)