Add a LagMeter (ticks per second) to the /gc command. This command can now be accessed with /lag as well. Also added a simple /vanish command, with the extra node essentials.vanish.see

If you require a more advanced vanish solution checkout VanishNoPacket from mbaxter.

Essentials/src/com/earth2me/essentials/Essentials.java

@@ -84,6 +84,7 @@ public class Essentials extends JavaPlugin implements IEssentials
 	private transient ExecuteTimer execTimer;
 	private transient I18n i18n;
 	private transient Metrics metrics;
+	private transient LagMeter lagMeter;
 
 	@Override
 	public ISettings getSettings()
@@ -240,6 +241,10 @@ public class Essentials extends JavaPlugin implements IEssentials
 
 		final EssentialsTimer timer = new EssentialsTimer(this);
 		getScheduler().scheduleSyncRepeatingTask(this, timer, 1, 100);
+
+		lagMeter = new LagMeter();
+		getScheduler().scheduleSyncRepeatingTask(this, lagMeter, 0, 40);
+
 		Economy.setEss(this);
 		execTimer.mark("RegListeners");
 
@@ -264,6 +269,13 @@ public class Essentials extends JavaPlugin implements IEssentials
 	@Override
 	public void onDisable()
 	{
+		for (Player p : getServer().getOnlinePlayers())
+		{
+			if (getUser(p).isVanished())
+			{
+				p.sendMessage(ChatColor.RED + _("unvanishedReload"));
+			}
+		}
 		i18n.onDisable();
 		Economy.setEss(null);
 		Trade.closeLog();
@@ -614,6 +626,10 @@ public class Essentials extends JavaPlugin implements IEssentials
 		return i18n;
 	}
 
+	public LagMeter getLagMeter()
+	{
+		return lagMeter;
+	}
 
 	private static class EssentialsWorldListener implements Listener, Runnable
 	{

Essentials/src/com/earth2me/essentials/IEssentials.java

@@ -71,4 +71,5 @@ public interface IEssentials extends Plugin
 	
 	void setMetrics(Metrics metrics);
 	
+	LagMeter getLagMeter();
 }

Essentials/src/com/earth2me/essentials/LagMeter.java

@@ -0,0 +1,44 @@
+package com.earth2me.essentials;
+
+import java.util.LinkedList;
+
+
+public class LagMeter implements Runnable
+{
+	private transient long lastPoll = System.currentTimeMillis() - 3000;
+	private final transient LinkedList<Float> history = new LinkedList<Float>();
+
+	@Override
+	public void run()
+	{
+		long now = System.currentTimeMillis();
+		long timeSpent = (now - lastPoll) / 1000;
+		if (timeSpent == 0)
+		{
+			timeSpent = 1;
+		}
+		if (history.size() > 10)
+		{
+			history.remove();
+		}
+		float tps = 40f / timeSpent;
+		if (tps <= 20)
+		{
+			history.add(tps);
+		}
+		lastPoll = now;
+	}
+
+	public float getAverageTPS()
+	{
+		float avg = 0;
+		for (Float f : history)
+		{
+			if (f != null)
+			{
+				avg += f;
+			}
+		}
+		return avg / history.size();
+	}
+}

Essentials/src/com/earth2me/essentials/User.java

@@ -17,6 +17,7 @@ public class User extends UserData implements Comparable<User>, IReplyTo, IUser
 	private CommandSender replyTo = null;
 	private transient User teleportRequester;
 	private transient boolean teleportRequestHere;
+	private transient boolean vanished;
 	private transient final Teleport teleport;
 	private transient long teleportRequestTime;
 	private transient long lastOnlineActivity;
@@ -640,4 +641,14 @@ public class User extends UserData implements Comparable<User>, IReplyTo, IUser
 	{
 		return teleportInvulnerabilityTimestamp != 0 && teleportInvulnerabilityTimestamp >= System.currentTimeMillis();
 	}
+
+	public boolean isVanished()
+	{
+		return vanished;
+	}
+
+	public void toggleVanished()
+	{
+		vanished = !vanished;
+	}
 }

Essentials/src/com/earth2me/essentials/commands/Commandgc.java

@@ -1,6 +1,7 @@
 package com.earth2me.essentials.commands;
 
 import static com.earth2me.essentials.I18n._;
+import org.bukkit.ChatColor;
 import org.bukkit.Server;
 import org.bukkit.World;
 import org.bukkit.command.CommandSender;
@@ -16,6 +17,21 @@ public class Commandgc extends EssentialsCommand
 	@Override
 	protected void run(final Server server, final CommandSender sender, final String commandLabel, final String[] args) throws Exception
 	{
+		float tps = ess.getLagMeter().getAverageTPS();
+		ChatColor color;
+		if (tps >= 18)
+		{
+			color = ChatColor.GREEN;
+		}
+		else if (tps >= 15)
+		{
+			color = ChatColor.YELLOW;
+		}
+		else
+		{
+			color = ChatColor.RED;
+		}
+		sender.sendMessage(_("tps", "" + color + tps));
 		sender.sendMessage(_("gcmax", (Runtime.getRuntime().maxMemory() / 1024 / 1024)));
 		sender.sendMessage(_("gctotal", (Runtime.getRuntime().totalMemory() / 1024 / 1024)));
 		sender.sendMessage(_("gcfree", (Runtime.getRuntime().freeMemory() / 1024 / 1024)));

Essentials/src/com/earth2me/essentials/commands/Commandvanish.java

@@ -0,0 +1,40 @@
+package com.earth2me.essentials.commands;
+
+import static com.earth2me.essentials.I18n._;
+import com.earth2me.essentials.User;
+import org.bukkit.ChatColor;
+import org.bukkit.Server;
+import org.bukkit.entity.Player;
+
+
+public class Commandvanish extends EssentialsCommand
+{
+	public Commandvanish()
+	{
+		super("vanish");
+	}
+
+	@Override
+	protected void run(Server server, User user, String commandLabel, String[] args) throws Exception
+	{
+		if (user.isVanished())
+		{
+			for (Player p : server.getOnlinePlayers())
+			{
+				p.showPlayer(user);
+			}
+			user.sendMessage(ChatColor.GREEN + _("vanished"));
+		}
+		else
+		{
+			for (Player p : server.getOnlinePlayers())
+			{
+				if (!ess.getUser(p).isAuthorized("essentials.vanish.see"))
+				{
+					p.hidePlayer(user);
+				}
+				user.sendMessage(ChatColor.GREEN + _("unvanished"));
+			}
+		}
+	}
+}

Essentials/src/messages.properties

@@ -364,6 +364,7 @@ tradeSignEmptyOwner=There is nothing to collect from this trade sign.
 treeFailure=\u00a7cTree generation failure. Try again on grass or dirt.
 treeSpawned=\u00a77Tree spawned.
 true=true
+tps=Current TPS = {0}
 typeTpaccept=\u00a77To teleport, type \u00a7c/tpaccept\u00a77.
 typeTpdeny=\u00a77To deny this request, type \u00a7c/tpdeny\u00a77.
 typeWorldName=\u00a77You can also type the name of a specific world.
@@ -377,6 +378,8 @@ unknownItemName=Unknown item name: {0}
 unlimitedItemPermission=\u00a7cNo permission for unlimited item {0}.
 unlimitedItems=Unlimited items:
 unmutedPlayer=Player {0} unmuted.
+unvanished=You are once again visible.
+unvanishedReload=A reload has forced you to become visible.
 upgradingFilesError=Error while upgrading the files
 userDoesNotExist=The user {0} does not exist.
 userIsAway={0} is now AFK
@@ -386,6 +389,7 @@ userUsedPortal={0} used an existing exit portal.
 userdataMoveBackError=Failed to move userdata/{0}.tmp to userdata/{1}
 userdataMoveError=Failed to move userdata/{0} to userdata/{1}.tmp
 usingTempFolderForTesting=Using temp folder for testing:
+vanished=You have now been vanished.
 versionMismatch=Version mismatch! Please update {0} to the same version.
 versionMismatchAll=Version mismatch! Please update all Essentials jars to the same version.
 voiceSilenced=\u00a77Your voice has been silenced

Essentials/src/plugin.yml

@@ -119,9 +119,9 @@ commands:
     usage: /<command> [player]
     aliases: [coords,egetpos,position,eposition,whereami,ewhereami]
   gc:
-    description: Reports garbage collection info; useful to developers.
+    description: Reports garbage collection and tick info; useful to developers.
     usage: /<command>
-    aliases: [mem,memory,egc,emem,ememory]
+    aliases: [elag,lag,mem,memory,egc,emem,ememory]
   give:
     description: Give a player an item.
     usage: /<command> <player> <item|numeric> [amount <enchantmentname[:level]> ...]
@@ -405,6 +405,10 @@ commands:
     description: Allows the unlimited placing of items.
     usage: /<command> <list|item|clear> [player]
     aliases: [eunlimited,ul,unl,eul,eunl]
+  vanish:
+    description: Hide yourself from other players.
+    usage: /<command>
+    aliases: [evanish]
   warp:
     description: List all warps or warp to the specified location.
     usage: /<command> <pagenumber|warp> [player]