daemons: revamp periodic cleanup task

Neither Inboxes nor ExtSearch objects were retrying correctly
when there are live git processes, but the inboxes were getting
rescanned for search or other reasons.  Ensure the scan retries
eventually if there's live processes.

We also need to update the cleanup task to detect Xapian shard
count changes, since Xapian ->reopen is enough to detect any
other Xapian changes.  Otherwise, we just issue an inexpensive
->reopen call and let Xapian check whether there's anything
worth reopening.

This also lets us eliminate the Devel::Peek dependency.

1 files changed, 9 insertions, 2 deletions

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index cf51239f..3c577ab3 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -400,7 +400,7 @@ sub cleanup {
         delete $self->{inflight_c};
         _destroy($self, qw(cat_rbuf in out pid));
         _destroy($self, qw(chk_rbuf in_c out_c pid_c err_c));
-        !!($self->{pid} || $self->{pid_c});
+        defined($self->{pid}) || defined($self->{pid_c});
 }
 
 
@@ -523,18 +523,25 @@ sub manifest_entry {
         $ent;
 }
 
+# returns true if there are pending cat-file processes
 sub cleanup_if_unlinked {
         my ($self) = @_;
         return cleanup($self) if $^O ne 'linux';
         # Linux-specific /proc/$PID/maps access
         # TODO: support this inside git.git
+        my $ret = 0;
         for my $fld (qw(pid pid_c)) {
                 my $pid = $self->{$fld} // next;
-                open my $fh, '<', "/proc/$pid/maps" or next;
+                open my $fh, '<', "/proc/$pid/maps" or return cleanup($self);
                 while (<$fh>) {
+                        # n.b. we do not restart for unlinked multi-pack-index
+                        # since it's not too huge, and the startup cost may
+                        # be higher.
                         return cleanup($self) if /\.(?:idx|pack) \(deleted\)$/;
                 }
+                ++$ret;
         }
+        $ret;
 }
 
 1;