Оптимизация RecyclerView AndroidStudio на Kotlin

Пишу что-то вроде социальной сети. Пользователь создаёт пост с картинкой и текстом, загружает его. Далее этот пост отображается в ленте RecyclerView. Адаптер задаёт информацию о пользователе, то есть имя, аватар:

private fun publisherInfo(profileImage: CircleImageView, userName: TextView, publisher: TextView, publisherID: String)
    {
        val usersRef = FirebaseDatabase.getInstance().reference.child("Users").child(publisherID)

        usersRef.addValueEventListener(object  : ValueEventListener
        {
            override fun onDataChange(p0: DataSnapshot)
            {
                if (p0.exists())
                {
                    val user = p0.getValue<User>(User::class.java)

                    Picasso.get().load(user!!.getImage()).into(profileImage)
                    userName.text = user!!.getUsername()
                    publisher.text = user!!.getFullname()
                }
            }

            override fun onCancelled(error: DatabaseError)
            {

            }
        })
    }

Если я использую Glide вместо Picasso, то вроде не так сильно тормозит, но делать я этого не могу из-за ряда причин. Сами посты отображаются во фрагменте:

private fun retrievePosts() {
        val postsRef = FirebaseDatabase.getInstance().reference.child("Posts")

        postsRef.addValueEventListener(object : ValueEventListener
        {
            override fun onDataChange(p0: DataSnapshot)
            {
               postList?.clear()

                for (snapshot in p0.children)
                {
                    val post = snapshot.getValue(Post::class.java)

                    for (id in (followingList as ArrayList<String>))
                    {
                        if (post!!.getPublisher() == id)
                        {
                            postList!!.add(post)
                        }

                        postAdapter!!.notifyDataSetChanged()
                    }
                }
            }

            override fun onCancelled(error: DatabaseError)
            {

            }
        })
    }

Но при прокрутке происходят ужасные зависания. Что мне делать?

class PostAdapter (private val mContext: Context, private val mPost: List) : RecyclerView.Adapter<PostAdapter.ViewHolder>() { private var firebaseUser: FirebaseUser? = null

var currentUserId: String = ""
var userId: String = ""


override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder
{
    val view = LayoutInflater.from(mContext).inflate(R.layout.posts_layout, parent, false)
    return ViewHolder(view)
}

override fun getItemCount(): Int {
    return mPost.size
}

@SuppressLint("WrongConstant")
@RequiresApi(Build.VERSION_CODES.O)
override fun onBindViewHolder(holder: ViewHolder, position: Int) {

    firebaseUser = FirebaseAuth.getInstance().currentUser

    currentUserId = FirebaseAuth.getInstance().currentUser!!.uid

    val post = mPost[position]

    Glide.with(mContext).load(post.getPostimage()).into(holder.postImage)

    if (post.getDescription().equals(""))
    {
        holder.description.visibility = View.GONE
    }
    else
    {
        holder.description.visibility = View.VISIBLE
        holder.description.setText(post.getDescription())
    }

    publisherInfo(holder.profileImage, holder.userName, holder.publisher, post.getPublisher())

}

inner class ViewHolder(@NonNull itemView: View) : RecyclerView.ViewHolder(itemView)
{
    var profileImage: CircleImageView
    var postImage: ImageView
    var userName: TextView
    var publisher: TextView
    var description: TextView

    init {
        profileImage = itemView.findViewById(R.id.user_profile_image_post)
        postImage = itemView.findViewById(R.id.post_image_content)
        userName = itemView.findViewById(R.id.username_post)
        publisher = itemView.findViewById(R.id.publisher)
        description = itemView.findViewById(R.id.description)
    }
}


private fun publisherInfo(profileImage: CircleImageView, userName: TextView, publisher: TextView, publisherID: String)
{
    val usersRef = FirebaseDatabase.getInstance().reference.child("Users").child(publisherID)

    usersRef.addValueEventListener(object  : ValueEventListener
    {
        override fun onDataChange(p0: DataSnapshot)
        {
            if (p0.exists())
            {
                val user = p0.getValue<User>(User::class.java)

                Picasso.get().load(user!!.getImage()).into(profileImage)
                userName.text = user!!.getUsername()
                publisher.text = user!!.getFullname()
            }
        }

        override fun onCancelled(error: DatabaseError)
        {

        }
    })
}

class User
{
    private var username: String = ""
    private var fullname: String = ""
    private var image: String = ""
    private var uid: String = ""

constructor()


constructor(username: String, fullname: String, image: String, uid: String)
{
    this.username = username
    this.fullname = fullname
    this.image = image
    this.uid = uid
}


fun getUsername(): String
{
    return username
}

fun setUsername(username: String)
{
    this.username = username
}

fun getFullname(): String
{
    return fullname
}

fun setFullname(fullname: String)
{
    this.fullname = fullname
}

fun getImage(): String
{
    return image
}

fun setImage(image: String)
{
    this.image = image
}

fun getUID(): String
{
    return uid
}

fun setUID(uid: String)
{
    this.uid = uid
}

}