Improve performance of discovery process

-Pull UDP queue in to remove duplicates
-Query all caches before slow refresh activities
-Decrease timeout on nodediscover notification
-Switch now only bothers refreshing a cache older than 20 seconds


git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@249 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

perl-xCAT-2.0/xCAT/MacMap.pm

@@ -84,6 +84,7 @@ sub find_mac {
 # and returns undef if unable to find the node, and the nodename otherwise
   my $self = shift;
   my $mac = shift;
+  my $cachedonly = shift;
 # For now HARDCODE (TODO, configurable?) a cache as stale after five minutes
 # Also, if things are changed in the config, our cache could be wrong, 
 # invalidate on switch table write?
@@ -91,12 +92,16 @@ sub find_mac {
     my $reftbl = 0;
     foreach (keys %{$self->{mactable}}) {
       if ((lc($mac) ne $_) and ($self->{mactable}->{lc($mac)} eq $self->{mactable}->{$_})) {
-        $reftbl = 1;
-        #The cache indicates confusion, flush it..
+        #$reftbl = 1;
+        #Delete *possibly* stale data, without being heavy handed..
+        delete $self->{mactable}->{$_};
       }
     }
     unless ($reftbl) { return $self->{mactable}->{lc($mac)};}
   }
+  #If requesting a cache only check or the cache is a mere 20 seconds old
+  #don't bother querying switches
+  if ($cachedonly or ($self->{timestamp} > (time() - 20))) { return undef; }
   $self->refresh_table; #not cached or stale cache, refresh
   if ($self->{mactable}->{lc($mac)}) {
     return $self->{mactable}->{lc($mac)};

xCAT-server-2.0/lib/xcat/plugins/blade.pm

@@ -884,7 +884,8 @@ sub process_request {
     }
     unless ($mac) { return };
 
-    unless ($macmap{$mac}) { 
+    #Only refresh the the cache when the request permits and no useful answer
+    unless ($request->{cacheonly}->[0] or $macmap{$mac}) { 
       process_request(\%invreq,\&fillresps);
     }
     unless ($macmap{$mac}) { 

xCAT-server-2.0/lib/xcat/plugins/nodediscover.pm

@@ -53,9 +53,10 @@ sub process_request {
   #now, notify the node to continue life
   my $sock = new IO::Socket::INET (
           PeerAddr => $ip,
-                  PeerPort => '3001',
-                          Proto => 'tcp'
-                                  );
+          PeerPort => '3001',
+          Timeout => '1',
+          Proto => 'tcp'
+    );
     unless ($sock) { syslog("err","Failed to notify $ip that it's actually $node."); return; } #Give up if the node won't hear of it.
     print $sock "restart";
     close($sock);

xCAT-server-2.0/lib/xcat/plugins/switch.pm

@@ -31,7 +31,7 @@ sub process_request {
  unless ($mac) {
    return;
  }
- my $node = $macmap->find_mac($mac);
+ my $node = $macmap->find_mac($mac,$req->{cacheonly}->[0]);
  if ($node) {
   my $mactab = xCAT::Table->new('mac',-create=>1);
   $mactab->setNodeAttribs($node,{mac=>$mac});

xCAT-server-2.0/sbin/xcatd

@@ -180,6 +180,7 @@ sub do_udp_service { #This function opens up a UDP port
   #Could be used for heartbeating and such as desired
 
 my $socket;
+   my $select = new IO::Select;
 if (xCAT::Utils->isLinux()) {
   $socket = IO::Socket::INET6->new(LocalPort => $port,
                                      Proto     => 'udp',
@@ -190,6 +191,7 @@ if (xCAT::Utils->isLinux()) {
                                      Domain => AF_INET);
 }
 
+  $select->add($socket);
   openlog("xCAT UDP",'','local4');
   unless ($socket) {
     syslog("err","xCAT UDP service unable to open port $port: $!");
@@ -201,9 +203,19 @@ if (xCAT::Utils->isLinux()) {
   my $sport;
   my $client;
   my $peerhost;
+  my %packets;
   until ($quit) {
-    eval { while ($part = $socket->recv($data,1500)) {
-        ($sport,$client) = sockaddr_in($part);
+    eval { 
+	while (1) {	
+        until ($select->can_read(5)) {} #Wait for data
+	while ($select->can_read(0)) { #Pull all buffer data that can be pulled
+	   $part = $socket->recv($data,1500);
+           ($sport,$client) = sockaddr_in($part);
+           $packets{inet_ntoa($client)} = [$part,$data];
+	}
+      foreach my $pkey (keys %packets) {
+        ($sport,$client) = sockaddr_in($packets{$pkey}->[0]);
+        $data=$packets{$pkey}->[1];
         $peerhost=gethostbyaddr($client,AF_INET)."\n";
         my $req = eval { XMLin($data, SuppressEmpty=>undef,ForceArray=>1) };
         if ($req and $req->{command} and ($req->{command}->[0] eq "findme")) {
@@ -211,11 +223,25 @@ if (xCAT::Utils->isLinux()) {
           $req->{'!xcat_clientip'}=inet_ntoa($client);
           $req->{'!xcat_clientport'}=$sport;
           if (defined($cmd_handlers{"findme"})) {
+            $req->{cacheonly}->[0] = 1;
             plugin_command($req,undef,\&convey_response);
+  	    if ($req->{cacheonly}->[0]) {
+		delete $req->{cacheonly};
+                plugin_command($req,undef,\&convey_response);
+	    }
           }
         }
         if ($quit) { last; }
+        while ($select->can_read(0)) { #grab any incoming requests during run
+	   $part = $socket->recv($data,1500);
+           ($sport,$client) = sockaddr_in($part);
+           $packets{inet_ntoa($client)} = [$part,$data];
+	}
+        #Some of those 'future' packets might be stale dupes of this packet, so...
+	delete $packets{$pkey}; #Delete any duplicates of current packet
       }
+      if ($quit) { last; }
+    }
     };
     if ($@) {
       syslog("local4|err","xcatd: possible BUG encountered by xCAT UDP service: ".$@);