serializers serialize rails fast example crear con active ruby-on-rails json ruby-on-rails-4 serialization active-model-serializers

ruby-on-rails - fast - rails serializer api



Active Model Serializer-Aumentar el rendimiento de render (2)

Cambie su consulta de ActiveRecord a esto

parent_comments = Comment.where(parent_comment_id: nil).includes(:user, children_comments: :user)

Se librará de las consultas de N + 1.

Estoy corriendo en una situación particular en la que el json generado generado por ActiveModel :: Serializer es extraordinariamente lento (alrededor de 6-8 segundos). ¿Cómo puedo mejorar la velocidad de este renderizado? Aquí está el código.

Modelos:

class Comment < ActiveRecord::Base has_many :children_comments, class_name: ''Comment'', foreign_key: ''parent_comment_id'' belongs_to :user belongs_to :parent_comment, class_name: ''Comment'', foreign_key: ''parent_comment_id'' end

Serializadores:

class CommentSerializer < ActiveModel::Serializer include ActionView::Helpers::DateHelper attributes :id, :message, :created_at_in_words, :created_at, :parent_comment_id belongs_to :user has_many :children_comments def created_at_in_words time_ago_in_words(object.created_at) + '' ago'' end def children_comments object.children_comments.map do |comment| CommentSerializer.new(comment).as_json end end end class UserSerializer < ActiveModel::Serializer attributes :id, :name, :avatar_url def avatar_url object.avatar.url end end

En mi controlador tengo

parent_comments = Comment.where(parent_comment_id: nil) render status: :ok, json: parent_comments, each_serializer: CommentSerializer, key_transform: :camel_lower

Aquí está mi salida parcial de registro cuando hago la llamada al servidor. Como puede ver, Active Model Serializer está tomando alrededor de 20 ms para hacer cada llamada de consulta.

Started GET "/comments?lesson_id=420" for ::1 at 2016-09-01 11:09:14 -0400 Processing by Api::CommentsController#index as HTML Parameters: {"lesson_id"=>"420"} User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 ORDER BY "users"."id" ASC LIMIT 1 [["id", 102]] Lesson Load (0.5ms) SELECT "lessons".* FROM "lessons" WHERE "lessons"."id" = $1 ORDER BY position ASC LIMIT 1 [["id", 420]] Comment Load (53.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."commentable_id" = $1 AND "comments"."commentable_type" = $2 AND "comments"."parent_comment_id" IS NULL [["commentable_id", 420], ["commentable_type", "Lesson"]] [active_model_serializers] User Load (0.5ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (24.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41401]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41402]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (22.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41403]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (21.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41404]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41405]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41406]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41407]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41408]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41409]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41410]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41411]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41412]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41413]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (23.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41414]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41415]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41416]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (23.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41417]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41418]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41419]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41420]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41421]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.9ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41422]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41423]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41424]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41425]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41426]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41427]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41428]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41429]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41430]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.9ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41431]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41432]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41433]] [active_model_serializers] CACHE (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (21.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41434]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41435]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (21.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41436]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41437]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41438]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (22.9ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41439]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41440]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41441]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.9ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41442]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41443]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41444]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41445]] [active_model_serializers] CACHE (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41446]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41447]] [active_model_serializers] CACHE (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41448]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41449]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41450]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41451]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41452]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41453]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41454]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (22.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41455]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (22.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41456]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41457]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41458]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41459]] [active_model_serializers] CACHE (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41460]] [active_model_serializers] CACHE (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41461]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41462]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41463]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41464]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41465]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41466]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41467]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.5ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41468]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41469]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41470]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41471]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41472]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41473]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41474]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41475]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41476]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (19.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41477]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41478]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41479]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.4ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41480]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.2ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41534]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41535]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.6ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41536]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.8ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41537]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (18.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 41538]] [active_model_serializers] Rendered ActiveModel::Serializer::CollectionSerializer with ActiveModelSerializers::Adapter::Json (3895.33ms) Completed 200 OK in 4007ms (Views: 1222.1ms | ActiveRecord: 2743.8ms)

Con la respuesta de Michal, aquí hay una pequeña muestra del registro.

Started GET "/comments?lesson_id=370" for ::1 at 2016-09-02 17:13:06 -0400 Processing by Api::CommentsController#index as HTML Parameters: {"lesson_id"=>"370"} User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 ORDER BY "users"."id" ASC LIMIT 1 [["id", 102]] Lesson Load (0.4ms) SELECT "lessons".* FROM "lessons" WHERE "lessons"."id" = $1 ORDER BY position ASC LIMIT 1 [["id", 370]] Comment Load (23.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" IS NULL AND "comments"."commentable_type" = ''Lesson'' AND "comments"."commentable_id" = 370 User Load (0.9ms) SELECT "users".* FROM "users" WHERE "users"."id" IN (102) Comment Load (25.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" IN (38641, 38687, 38733) CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" IN (102) [active_model_serializers] Comment Load (20.3ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 38642]] [active_model_serializers] User Load (0.5ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (20.7ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 38643]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]] [active_model_serializers] Comment Load (30.1ms) SELECT "comments".* FROM "comments" WHERE "comments"."parent_comment_id" = $1 [["parent_comment_id", 38644]] [active_model_serializers] CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1 [["id", 102]]

Mi teoría es la siguiente. Estoy convencido de que la serialización children_comments está causando la mayoría de los problemas de rendimiento. Como tengo que llamar a children_comments para cada comentario, esto produce un efecto de cascada. Me pregunto si puedo reescribir el código para mejorar el rendimiento.

Te encuentras con un problema de tipo n + 1 consultas. Desafortunadamente, includes realmente no lo está ayudando aquí porque solo lo ayuda con un nivel de la asociación; evita capturas separadas de los niños del comentario de nivel superior, pero no nietos ni bisnietos.

Probablemente pueda optimizar la búsqueda del usuario manteniendo su propio caché de identificación de usuario para los objetos del usuario (el caché de los rieles almacena en caché los datos en bruto, pero reintegrará los objetos una y otra vez), pero para que esto sea sustancialmente más rápido, debe cambiar la forma en que cargar los comentarios.

Si está utilizando una base de datos que la admite (como postgresql), las consultas recursivas son una opción (consulte https://hashrocket.com/blog/posts/recursive-sql-in-activerecord para ver un ejemplo). No sé estas escalas a medida que el árbol se hace más y más profundo.

Si las consultas recursivas no son una opción, hay algunos enfoques que implican cambiar lo que almacena.

Uno es el camino materializado patten. Por ejemplo, digamos que el comentario raíz tiene id 1, un hijo tiene id 101 y uno de sus hijos tiene id 426. La ruta del último comentario es 1/101/426 . Todos sus hermanos tienen caminos que comienzan con 1/101/ . Esto significa que puede usar consultas similares (con comodines al final) para encontrar subárboles rápidamente. La gema de la ancestry implementa esto. Si los comentarios se mueven, deberá volver a escribir las rutas de todos los comentarios niños (y nietos, etc.), pero eso puede no ser relevante para su caso de uso. Los árboles muy profundos son problemáticos, creo.

Otro es el patrón de conjunto anidado. La idea central es que el nodo padre almacena la identificación mínima y máxima de todos sus hijos y los hijos de sus hijos, etc. Esto permite recuperar a todos estos niños de una sola vez. La otra cara es que las inserciones y actualizaciones requieren volver a escribir muchos de estos datos (más que con la ruta materializada). Ha habido varias gemas que implementan esto a lo largo de los años (una actual parece ser awesome_nested_set ).

También vale la pena comprobar que tiene los índices correctos para respaldar sus consultas, a menos que realmente haya muchos comentarios con un padre determinado, 20-30 ms parece bastante tiempo para una consulta.