How to Improve RecyclerView Performance in Android Using DiffUtil?

// this is the Language model class
class Language(
    val id : Int =0,
    val name : String ="",
    val exp : String =""
)

import androidx.recyclerview.widget.DiffUtil

// pass two list one oldList and second newList
class MyDiffUtil(
    private val oldList : List<Language>,
    private val newList : List<Language>
) :DiffUtil.Callback() {
    // implement methods
    override fun getOldListSize(): Int {
        // return oldList size
        return oldList.size
    }

    override fun getNewListSize(): Int {
        // return newList size
        return newList.size
    }

    override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
        // compare items based on their unique id
        return oldList[oldItemPosition].id == newList[newItemPosition].id
    }

    override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
        // in here compare each item if they are same or different
        // return false if any data is same else return true
        return when{
            oldList[oldItemPosition].id != newList[newItemPosition].id -> false
            oldList[oldItemPosition].name != newList[newItemPosition].name -> false
            oldList[oldItemPosition].exp != newList[newItemPosition].exp -> false
            else -> true
        }
    }
}

import android.view.LayoutInflater
import android.view.ViewGroup
import androidx.recyclerview.widget.DiffUtil
import androidx.recyclerview.widget.RecyclerView
import com.geeksforgeeks.rvadapterviewbinding.databinding.SingleItemBinding

class RvAdapter() : RecyclerView.Adapter<RvAdapter.ViewHolder>() {

    private var oldLanguageList= emptyList<Language>()
    // create an inner class with name ViewHolder
    // It takes a view argument, in which pass the generated class of single_item.xml
    // ie SingleItemBinding and in the RecyclerView.ViewHolder(binding.root) pass it like this
    inner class ViewHolder(val binding: SingleItemBinding) : RecyclerView.ViewHolder(binding.root)

    // inside the onCreateViewHolder inflate the view of SingleItemBinding
    // and return new ViewHolder object containing this layout
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        val binding = SingleItemBinding.inflate(LayoutInflater.from(parent.context), parent, false)
        return ViewHolder(binding)
    }

    // bind the items with each item of the list languageList which than will be
    // shown in recycler view
    // to keep it simple we are not setting any image data to view
    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        with(holder){
            with(oldLanguageList[position]){
                binding.tvLangName.text = this.name
                binding.tvExp.text = this.exp
            }
        }
    }

    // return the size of languageList
    override fun getItemCount(): Int {
        return oldLanguageList.size
    }

    fun setData(newLanguageList : List<Language>){
        val diffUtil = MyDiffUtil(oldLanguageList , newLanguageList)
        // it calculates the different items of the oldLanguageList and newLanguageList
        val diffResult = DiffUtil.calculateDiff(diffUtil)
        // assign oldLanguageList to newLanguageList
        oldLanguageList = newLanguageList
        diffResult.dispatchUpdatesTo(this)
    }
}

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.recyclerview.widget.LinearLayoutManager
import com.geeksforgeeks.rvadapterviewbinding.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

    // view binding for the activity
    private var _binding : ActivityMainBinding? = null
    private val binding get() = _binding!!

    // get reference to the adapter class
    private val rvAdapter by lazy { RvAdapter() }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        _binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)

        // define layout manager for the Recycler view
        binding.rvList.layoutManager = LinearLayoutManager(this)
        
        // attach adapter to the recycler view
        binding.rvList.adapter = rvAdapter

        // create new objects
        val language1= Language(1,"Java" , "Exp : 3 years")
        val language2=Language(2,"Kotlin" , "Exp : 2 years")
        val language3=Language(3,"Python" , "Exp : 4 years")

        // call set data method of adapter class and the list data
        rvAdapter.setData(listOf(language1, language2, language3))
        binding.btnNewLanguage.setOnClickListener {
            // on click of button add one more item to the list
            val language4= Language(4,"CPP" , "Exp : 5 years")
            rvAdapter.setData(listOf(language1,language2,language3,language4))
        }
    }

    // on destroy of view make the binding reference to null
    override fun onDestroy() {
        super.onDestroy()
        _binding = null
    }
}