Introduce an educated guess comment on why reflog is disabled on replicas
When repositories are replicated, their reflog is turned off on the
replica side. Add a comment explaining why that choice was possibly made
over a decade ago.
The author of the change is Shawn who passed years ago. The change did
not go through reviews at that time so there is no track record of the
choice.
Change-Id: I04de480df0d6012e3a4539fda945d15fc3f4eaa3
diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/LocalFS.java b/src/main/java/com/googlesource/gerrit/plugins/replication/LocalFS.java
index 49c97f0..932d907 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/LocalFS.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/LocalFS.java
@@ -46,6 +46,11 @@
repo.create(true /* bare */);
if (head != null && head.startsWith(Constants.R_REFS)) {
+ // It is unclear why the reflog is disabled when updating the HEAD. It has been like that
+ // for over a decade and does not cause issues so far.
+ // One educated guess is that it follows the default of the git config option
+ // core.logAllRefUpdates which is false by default for bare repositories and by default
+ // stores reflogs only for repositories which have a working tree.
RefUpdate u = repo.updateRef(Constants.HEAD);
u.disableRefLog();
u.link(head);
