[backend] avoid sending events to disabled archs

we collect endless event files otherwise

src/backend/BSConfiguration.pm

@@ -41,11 +41,12 @@ $bsconfigvalues{'forceprojectkeys'} = 1 if defined $BSConfig::forceprojectkeys;
 my $configurationid = '';
 my $configuration_file = "$BSConfig::bsdir/configuration.xml";
 my $confiuration_checked_once;
+our $xml;
 
 sub update_from_configuration {
   my @s = stat($configuration_file);
   $configurationid = @s ? "$s[9]/$s[7]/$s[1]" : '';
-  my $xml = readxml($configuration_file, $BSXML::configuration, 1) || {};
+  $xml = readxml($configuration_file, $BSXML::configuration, 1) || {};
   $BSConfig::obsname = $xml->{'name'} unless $bsconfigvalues{'obsname'};
   $BSConfig::proxy = $xml->{'http_proxy'} unless $bsconfigvalues{'proxy'};
   $BSConfig::noproxy = $xml->{'no_proxy'} unless $bsconfigvalues{'noproxy'};

src/backend/bs_admin

@@ -36,7 +36,7 @@ use XML::Structured ':bytes';
 
 use Build;
 
-use BSConfig;
+use BSConfiguration;
 use BSFileDB;
 use BSWatcher;
 use BSUtil;

src/backend/bs_repserver

@@ -2128,8 +2128,14 @@ sub forwardevent {
     writexml("$eventdir/$arch/.$evname.$$", "$eventdir/$arch/$evname", $ev, $BSXML::event);
     BSUtil::ping("$eventdir/$arch/.ping");
   } else {
-    # XXX: there should be a better way than to just write in all
-    # directories... maybe a architecture list in BSConfig?
+    my @archs;
+    if ($BSConfiguration::xml->{'schedulers'} && $BSConfiguration::xml->{'schedulers'}->{'arch'}) {
+      # notify only active schedulers
+      @archs = @{$BSConfiguration::xml->{'schedulers'}->{'arch'}};
+    } else {
+      # unconfigured, fallback to all existing directories
+      @archs = ls($eventdir);
+    }
     for my $a (ls($eventdir)) {
       next if $a =~ /^\./;
       next unless -d "$eventdir/$a";