Some Scoreboard trouble

I've been working on a server for quite some time now, and I have gotten everything down, accept for my custom plugin's Scoreboard. I have a scoreboard that's working, but it puts the CPU under so much stress that the server can barely run. The CPU usage, with 3 people on goes from 1% to ~30%. I've found that the issue is with the scoreboard. This is the code that I have updating every 3 seconds that appears to be causing the lag:

Code:java

package com.melonmc.kitpvp;
import java.util.HashMap;
 
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerQuitEvent;
import org.bukkit.scoreboard.DisplaySlot;
import org.bukkit.scoreboard.Objective;
import org.bukkit.scoreboard.Score;
import org.bukkit.scoreboard.Scoreboard;
import org.bukkit.scoreboard.ScoreboardManager;
 
import com.melonmc.kitpvp.Main;
 
 
public class BoardManagement implements Listener{
 
    Main plugin;
 
    public BoardManagement(Main main){
        plugin = main;
    }
 
    ScoreboardManager manager;
 
    HashMap<String, Scoreboard> playerScoreboards = new HashMap<String, Scoreboard>();
 
    @EventHandler
    public void onQuit(PlayerQuitEvent event){
        Player player = event.getPlayer();
        if(playerScoreboards.containsKey(player.getName())){
            playerScoreboards.remove(player.getName());
        }
    }
 
    public void updateScores(){
        for(Player player:Bukkit.getOnlinePlayers()){
            if(playerScoreboards.containsKey(player.getName())){
                Scoreboard board = playerScoreboards.get(player.getName());
                Objective objective = board.getObjective(DisplaySlot.SIDEBAR);
 
                Score scoreKills = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Kills:"));
                Score scoreDeaths = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Deaths:"));
                Score scoreCredits = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Credits:"));
                Score scoreWorth = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Worth:"));
                Score scoreKS = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Kill Streak:"));
 
                scoreKS.setScore(plugin.cm.KS.get(player) != null ? plugin.cm.KS.get(player):0);
                scoreDeaths.setScore((int)plugin.cm.getDeaths(player));
                scoreKills.setScore((int)plugin.cm.getKills(player));
                scoreCredits.setScore((int)plugin.cm.getCredits(player));
                scoreWorth.setScore((int)plugin.cm.getWorth(player));
            }else{
                manager = Bukkit.getScoreboardManager();
                Scoreboard board = manager.getNewScoreboard();
                Objective objective = board.registerNewObjective("stats", "dummy");
 
                board.clearSlot(DisplaySlot.SIDEBAR);
                objective.setDisplaySlot(DisplaySlot.SIDEBAR);
                objective.setDisplayName(ChatColor.GOLD + player.getName() + "");
 
                Score scoreKills = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Kills:"));
                Score scoreDeaths = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Deaths:"));
                Score scoreCredits = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Credits:"));
                Score scoreWorth = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Worth:"));
                Score scoreKS = objective.getScore(Bukkit.getOfflinePlayer(ChatColor.GREEN + "Kill Streak:"));
 
                scoreKS.setScore(plugin.cm.KS.get(player) != null ? plugin.cm.KS.get(player):0);
                scoreDeaths.setScore((int)plugin.cm.getDeaths(player));
                scoreKills.setScore((int)plugin.cm.getKills(player));
                scoreCredits.setScore((int)plugin.cm.getCredits(player));
                scoreWorth.setScore((int)plugin.cm.getWorth(player));
 
                player.setScoreboard(board);
                playerScoreboards.put(player.getName(), board);
            }
        }
    }
 
}

If you can help me in any way or if you need any more info please let me know.

 

Why are you updating every 3 seconds , why not just update on a entity death?.

You're looping through all players that have ever been on your server, and every 3 seconds that is unneeded

 

I'll give it a shot, thanks.