watch: avoid unnecessary spawning on spam removals

[public-inbox.git] / lib / PublicInbox / Watch.pm

diff --git a/lib/PublicInbox/Watch.pm b/lib/PublicInbox/Watch.pm
index 5f78613961db1058506b8193c4ea7bd55c0522f3..0bb92d0a9055703233b7af5cafe53bdfa0232e2f 100644 (file)
--- a/lib/PublicInbox/Watch.pm
+++ b/lib/PublicInbox/Watch.pm
@@ -134,15 +134,34 @@ sub _done_for_now {
 sub remove_eml_i { # each_inbox callback
        my ($ibx, $arg) = @_;
        my ($self, $eml, $loc) = @$arg;
+
        eval {
-               my $im = _importer_for($self, $ibx);
-               $im->remove($eml, 'spam');
-               if (my $scrub = $ibx->filter($im)) {
-                       my $scrubbed = $scrub->scrub($eml, 1);
-                       if ($scrubbed && $scrubbed != REJECT) {
-                               $im->remove($scrubbed, 'spam');
+               # try to avoid taking a lock or unnecessary spawning
+               my $im = $self->{importers}->{"$ibx"};
+               my $scrubbed;
+               if ((!$im || !$im->active) && $ibx->over) {
+                       if (content_exists($ibx, $eml)) {
+                               # continue
+                       } elsif (my $scrub = $ibx->filter($im)) {
+                               $scrubbed = $scrub->scrub($eml, 1);
+                               if ($scrubbed && $scrubbed != REJECT &&
+                                         !content_exists($ibx, $scrubbed)) {
+                                       return;
+                               }
+                       } else {
+                               return;
                        }
                }
+
+               $im //= _importer_for($self, $ibx); # may spawn fast-import
+               $im->remove($eml, 'spam');
+               $scrubbed //= do {
+                       my $scrub = $ibx->filter($im);
+                       $scrub ? $scrub->scrub($eml, 1) : undef;
+               };
+               if ($scrubbed && $scrubbed != REJECT) {
+                       $im->remove($scrubbed, 'spam');
+               }
        };
        if ($@) {
                warn "error removing spam at: $loc from $ibx->{name}: $@\n";