From a5c8a52782ae6e948adbbba77c0ec702ffe28ae1 Mon Sep 17 00:00:00 2001 From: Yorick Peterse Date: Wed, 9 Aug 2017 15:49:30 +0200 Subject: [PATCH] Better caching and indexing of broadcast messages Caching of BroadcastMessage instances has been changed so a cache stays valid as long as the default cache expiration time permits, instead of the cache being expired after 1 minute. When modifying broadcast messages the cache is flushed automatically. To remove the need for performing sequence scans on the "broadcast_messages" table we also add an index on (starts_at, ends_at, id), permitting PostgreSQL to use an index scan to get all necessary data. Finally this commit adds a few NOT NULL constraints to the table to match the Rails validations. Fixes gitlab-org/gitlab-ce#31706 --- app/models/broadcast_message.rb | 14 +++++++++++-- .../unreleased/broadcast-messages-cache.yml | 4 ++++ ...0809133343_add_broadcast_messages_index.rb | 21 +++++++++++++++++++ ..._broadcast_message_not_null_constraints.rb | 17 +++++++++++++++ db/schema.rb | 12 ++++++----- spec/models/broadcast_message_spec.rb | 20 +++++++++++++++++- 6 files changed, 80 insertions(+), 8 deletions(-) create mode 100644 changelogs/unreleased/broadcast-messages-cache.yml create mode 100644 db/migrate/20170809133343_add_broadcast_messages_index.rb create mode 100644 db/migrate/20170809134534_add_broadcast_message_not_null_constraints.rb diff --git a/app/models/broadcast_message.rb b/app/models/broadcast_message.rb index 944725d91c3..3692bcc680d 100644 --- a/app/models/broadcast_message.rb +++ b/app/models/broadcast_message.rb @@ -14,9 +14,15 @@ class BroadcastMessage < ActiveRecord::Base default_value_for :color, '#E75E40' default_value_for :font, '#FFFFFF' + CACHE_KEY = 'broadcast_message_current'.freeze + + after_commit :flush_redis_cache + def self.current - Rails.cache.fetch("broadcast_message_current", expires_in: 1.minute) do - where('ends_at > :now AND starts_at <= :now', now: Time.zone.now).order([:created_at, :id]).to_a + Rails.cache.fetch(CACHE_KEY) do + where('ends_at > :now AND starts_at <= :now', now: Time.zone.now) + .reorder(id: :asc) + .to_a end end @@ -31,4 +37,8 @@ class BroadcastMessage < ActiveRecord::Base def ended? ends_at < Time.zone.now end + + def flush_redis_cache + Rails.cache.delete(CACHE_KEY) + end end diff --git a/changelogs/unreleased/broadcast-messages-cache.yml b/changelogs/unreleased/broadcast-messages-cache.yml new file mode 100644 index 00000000000..a3c9e1ff465 --- /dev/null +++ b/changelogs/unreleased/broadcast-messages-cache.yml @@ -0,0 +1,4 @@ +--- +title: Better caching and indexing of broadcast messages +merge_request: +author: diff --git a/db/migrate/20170809133343_add_broadcast_messages_index.rb b/db/migrate/20170809133343_add_broadcast_messages_index.rb new file mode 100644 index 00000000000..4ab2ddb059d --- /dev/null +++ b/db/migrate/20170809133343_add_broadcast_messages_index.rb @@ -0,0 +1,21 @@ +# See http://doc.gitlab.com/ce/development/migration_style_guide.html +# for more information on how to write migrations for GitLab. + +class AddBroadcastMessagesIndex < ActiveRecord::Migration + include Gitlab::Database::MigrationHelpers + + # Set this constant to true if this migration requires downtime. + DOWNTIME = false + + disable_ddl_transaction! + + COLUMNS = %i[starts_at ends_at id].freeze + + def up + add_concurrent_index :broadcast_messages, COLUMNS + end + + def down + remove_concurrent_index :broadcast_messages, COLUMNS + end +end diff --git a/db/migrate/20170809134534_add_broadcast_message_not_null_constraints.rb b/db/migrate/20170809134534_add_broadcast_message_not_null_constraints.rb new file mode 100644 index 00000000000..13e8ef52f22 --- /dev/null +++ b/db/migrate/20170809134534_add_broadcast_message_not_null_constraints.rb @@ -0,0 +1,17 @@ +# See http://doc.gitlab.com/ce/development/migration_style_guide.html +# for more information on how to write migrations for GitLab. + +class AddBroadcastMessageNotNullConstraints < ActiveRecord::Migration + include Gitlab::Database::MigrationHelpers + + # Set this constant to true if this migration requires downtime. + DOWNTIME = false + + COLUMNS = %i[starts_at ends_at created_at updated_at message_html] + + def change + COLUMNS.each do |column| + change_column_null :broadcast_messages, column, false + end + end +end diff --git a/db/schema.rb b/db/schema.rb index 65afe37a21c..9d3b3ad1826 100644 --- a/db/schema.rb +++ b/db/schema.rb @@ -163,16 +163,18 @@ ActiveRecord::Schema.define(version: 20170809142252) do create_table "broadcast_messages", force: :cascade do |t| t.text "message", null: false - t.datetime "starts_at" - t.datetime "ends_at" - t.datetime "created_at" - t.datetime "updated_at" + t.datetime "starts_at", null: false + t.datetime "ends_at", null: false + t.datetime "created_at", null: false + t.datetime "updated_at", null: false t.string "color" t.string "font" - t.text "message_html" + t.text "message_html", null: false t.integer "cached_markdown_version" end + add_index "broadcast_messages", ["starts_at", "ends_at", "id"], name: "index_broadcast_messages_on_starts_at_and_ends_at_and_id", using: :btree + create_table "chat_names", force: :cascade do |t| t.integer "user_id", null: false t.integer "service_id", null: false diff --git a/spec/models/broadcast_message_spec.rb b/spec/models/broadcast_message_spec.rb index a8ca1d110e4..3369aef1d3e 100644 --- a/spec/models/broadcast_message_spec.rb +++ b/spec/models/broadcast_message_spec.rb @@ -20,7 +20,7 @@ describe BroadcastMessage do it { is_expected.not_to allow_value('000').for(:font) } end - describe '.current' do + describe '.current', :use_clean_rails_memory_store_caching do it 'returns message if time match' do message = create(:broadcast_message) @@ -45,6 +45,14 @@ describe BroadcastMessage do expect(described_class.current).to be_empty end + + it 'caches the output of the query' do + create(:broadcast_message) + + expect(described_class).to receive(:where).and_call_original.once + + 2.times { described_class.current } + end end describe '#active?' do @@ -102,4 +110,14 @@ describe BroadcastMessage do end end end + + describe '#flush_redis_cache' do + it 'flushes the Redis cache' do + message = create(:broadcast_message) + + expect(Rails.cache).to receive(:delete).with(described_class::CACHE_KEY) + + message.flush_redis_cache + end + end end