extindex: retry sync_inbox before reindex

Ensure the num highwater mark of the target inbox is stable
before using it.  Otherwise we may end up repeating work
done to index a message.

diff --git a/lib/PublicInbox/ExtSearchIdx.pm b/lib/PublicInbox/ExtSearchIdx.pm
index 67d720368922d6013253fc4be27c7464c02f3265..daff656d1ac54749090a137a85ea8a8542564a68 100644 (file)
--- a/lib/PublicInbox/ExtSearchIdx.pm
+++ b/lib/PublicInbox/ExtSearchIdx.pm
@@ -859,14 +859,20 @@ sub _reindex_check_ibx ($$$) {
        my $slice = 10000;
        my $opt = { limit => $slice };
        my ($beg, $end) = (1, $slice);
-       my $err = sync_inbox($self, $sync, $ibx) and return;
-       my $max = $ibx->mm->num_highwater;
+       my $ekey = $ibx->eidx_key;
+       my ($max, $max0);
+       do {
+               $max0 = $ibx->mm->num_highwater;
+               sync_inbox($self, $sync, $ibx) and return; # warned
+               $max = $ibx->mm->num_highwater;
+               return if $sync->{quit};
+       } while ($max > $max0 &&
+               warn("# $ekey moved $max0..$max, resyncing..\n"));
        $end = $max if $end > $max;
 
        # first, check if we missed any messages in target $ibx
        my $msgs;
        my $pr = $sync->{-opt}->{-progress};
-       my $ekey = $ibx->eidx_key;
        local $sync->{-regen_fmt} = "$ekey checking %u/$max\n";
        ${$sync->{nr}} = 0;
        my $fast = $sync->{-opt}->{fast};