Fix performances of profile directory

app/models/account.rb

@@ -125,7 +125,7 @@ class Account < ApplicationRecord
   scope :matches_domain, ->(value) { where(arel_table[:domain].matches("%#{value}%")) }
   scope :without_unapproved, -> { left_outer_joins(:user).merge(User.approved.confirmed).or(remote) }
   scope :searchable, -> { without_unapproved.without_suspended.where(moved_to_account_id: nil) }
-  scope :discoverable, -> { searchable.without_silenced.where(discoverable: true).left_outer_joins(:account_stat) }
+  scope :discoverable, -> { searchable.without_silenced.where(discoverable: true).joins(:account_stat) }
   scope :followable_by, ->(account) { joins(arel_table.join(Follow.arel_table, Arel::Nodes::OuterJoin).on(arel_table[:id].eq(Follow.arel_table[:target_account_id]).and(Follow.arel_table[:account_id].eq(account.id))).join_sources).where(Follow.arel_table[:id].eq(nil)).joins(arel_table.join(FollowRequest.arel_table, Arel::Nodes::OuterJoin).on(arel_table[:id].eq(FollowRequest.arel_table[:target_account_id]).and(FollowRequest.arel_table[:account_id].eq(account.id))).join_sources).where(FollowRequest.arel_table[:id].eq(nil)) }
   scope :by_recent_status, -> { order(Arel.sql('account_stats.last_status_at DESC NULLS LAST')) }
   scope :by_recent_sign_in, -> { order(Arel.sql('users.current_sign_in_at DESC NULLS LAST')) }

db/migrate/20230907150100_add_index_account_stats_on_last_status_at_and_account_id.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddIndexAccountStatsOnLastStatusAtAndAccountId < ActiveRecord::Migration[7.0]
+  disable_ddl_transaction!
+
+  def change
+    add_index :account_stats, [:last_status_at, :account_id], order: { last_status_at: 'DESC NULLS LAST' }, algorithm: :concurrently
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2023_09_04_134623) do
+ActiveRecord::Schema[7.0].define(version: 2023_09_07_150100) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -99,6 +99,7 @@
     t.datetime "updated_at", precision: nil, null: false
     t.datetime "last_status_at", precision: nil
     t.index ["account_id"], name: "index_account_stats_on_account_id", unique: true
+    t.index ["last_status_at", "account_id"], name: "index_account_stats_on_last_status_at_and_account_id", order: { last_status_at: "DESC NULLS LAST" }
   end
 
   create_table "account_statuses_cleanup_policies", force: :cascade do |t|

spec/controllers/api/v1/directories_controller_spec.rb

@@ -15,43 +15,48 @@
   describe 'GET #show' do
     context 'with no params' do
       before do
-        _local_unconfirmed_account = Fabricate(
+        local_unconfirmed_account = Fabricate(
           :account,
           domain: nil,
           user: Fabricate(:user, confirmed_at: nil, approved: true),
           username: 'local_unconfirmed'
         )
+        local_unconfirmed_account.create_account_stat!
 
         local_unapproved_account = Fabricate(
           :account,
           domain: nil,
           user: Fabricate(:user, confirmed_at: 10.days.ago),
           username: 'local_unapproved'
         )
+        local_unapproved_account.create_account_stat!
         local_unapproved_account.user.update(approved: false)
 
-        _local_undiscoverable_account = Fabricate(
+        local_undiscoverable_account = Fabricate(
           :account,
           domain: nil,
           user: Fabricate(:user, confirmed_at: 10.days.ago, approved: true),
           discoverable: false,
           username: 'local_undiscoverable'
         )
+        local_undiscoverable_account.create_account_stat!
 
         excluded_from_timeline_account = Fabricate(
           :account,
           domain: 'host.example',
           discoverable: true,
           username: 'remote_excluded_from_timeline'
         )
+        excluded_from_timeline_account.create_account_stat!
         Fabricate(:block, account: user.account, target_account: excluded_from_timeline_account)
 
-        _domain_blocked_account = Fabricate(
+        domain_blocked_account = Fabricate(
           :account,
           domain: 'test.example',
           discoverable: true,
           username: 'remote_domain_blocked'
         )
+        domain_blocked_account.create_account_stat!
         Fabricate(:account_domain_block, account: user.account, domain: 'test.example')
       end
 
@@ -63,13 +68,15 @@
           discoverable: true,
           username: 'local_discoverable'
         )
+        local_discoverable_account.create_account_stat!
 
         eligible_remote_account = Fabricate(
           :account,
           domain: 'host.example',
           discoverable: true,
           username: 'eligible_remote'
         )
+        eligible_remote_account.create_account_stat!
 
         get :show
 
@@ -84,6 +91,8 @@
         user = Fabricate(:user, confirmed_at: 10.days.ago, approved: true)
         local_account = Fabricate(:account, domain: nil, user: user)
         remote_account = Fabricate(:account, domain: 'host.example')
+        local_account.create_account_stat!
+        remote_account.create_account_stat!
 
         get :show, params: { local: '1' }
 
@@ -110,9 +119,9 @@
 
     context 'when ordered by new' do
       it 'returns accounts in order of creation' do
-        account_old = Fabricate(:account)
+        account_old = Fabricate(:account_stat).account
         travel_to 10.seconds.from_now
-        account_new = Fabricate(:account)
+        account_new = Fabricate(:account_stat).account
 
         get :show, params: { order: 'new' }