[PATCH] doc: recommend -compact after --reindex

[Eric Wong <e@yhbt.net>]

It's likely a user will be low on space after running --reindex,
so recommend the use of public-inbox-compact afterwards.

And add a few more notes about using public-inbox-compact to
clarify it's for inboxes-only (and not any old Xapian DBs) that
using xapian-compact(1) directly is error-prone and likely to
break things.
---
 Documentation/public-inbox-compact.pod | 5 +++--
 Documentation/public-inbox-index.pod   | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/Documentation/public-inbox-compact.pod b/Documentation/public-inbox-compact.pod
index 20f9d475..6b0c7376 100644
--- a/Documentation/public-inbox-compact.pod
+++ b/Documentation/public-inbox-compact.pod
@@ -1,6 +1,6 @@
 =head1 NAME
 
-public-inbox-compact - compact Xapian DBs
+public-inbox-compact - compact Xapian DBs in an inbox
 
 =head1 SYNOPSIS
 
@@ -14,7 +14,8 @@ L<public-inbox-watch(1)> or L<public-inbox-mda(1)> from
 writing while it operates.
 
 It enforces the use of the C<--no-renumber> option of
-L<xapian-compact(1)>
+L<xapian-compact(1)> which is required to work with the
+rest of the public-inbox search code.
 
 =head1 OPTIONS
 
diff --git a/Documentation/public-inbox-index.pod b/Documentation/public-inbox-index.pod
index 610dacbe..6dc6a3aa 100644
--- a/Documentation/public-inbox-index.pod
+++ b/Documentation/public-inbox-index.pod
@@ -38,7 +38,8 @@ Forces a search engine re-index of all messages in the
 repository.  This can be used for in-place upgrades while
 NNTP/HTTP server processes are utilizing the index.  Keep in
 mind this roughly doubles the size of the already-large
-Xapian database.
+Xapian database.  Running L<public-inbox-compact(1)>
+afterwards is recommended to release free space.
 
 This does not touch the NNTP article number database.