diff --git a/changelogs/unreleased/ci-builds-status-index.yml b/changelogs/unreleased/ci-builds-status-index.yml
new file mode 100644
index 0000000000000000000000000000000000000000..8b7252f09e5be167b29f74948233263dd957280c
--- /dev/null
+++ b/changelogs/unreleased/ci-builds-status-index.yml
@@ -0,0 +1,5 @@
+---
+title: Remove redundant ci_builds (status) index
+merge_request: 21070
+author:
+type: performance
diff --git a/db/migrate/20180807153545_remove_redundant_status_index_on_ci_builds.rb b/db/migrate/20180807153545_remove_redundant_status_index_on_ci_builds.rb
new file mode 100644
index 0000000000000000000000000000000000000000..f4f7cb6f8ca791a37e93501ae04a9f6bb5ea8d61
--- /dev/null
+++ b/db/migrate/20180807153545_remove_redundant_status_index_on_ci_builds.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class RemoveRedundantStatusIndexOnCiBuilds < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    remove_concurrent_index :ci_builds, :status
+  end
+
+  def down
+    add_concurrent_index :ci_builds, :status
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index c132f78753073e1f5d75e031340f3b2dcbcabe21..f1d8f4df3b753487406f453a92b9547324e21904 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20180726172057) do
+ActiveRecord::Schema.define(version: 20180807153545) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -346,7 +346,6 @@ ActiveRecord::Schema.define(version: 20180726172057) do
   add_index "ci_builds", ["stage_id", "stage_idx"], name: "tmp_build_stage_position_index", where: "(stage_idx IS NOT NULL)", using: :btree
   add_index "ci_builds", ["stage_id"], name: "index_ci_builds_on_stage_id", using: :btree
   add_index "ci_builds", ["status", "type", "runner_id"], name: "index_ci_builds_on_status_and_type_and_runner_id", using: :btree
-  add_index "ci_builds", ["status"], name: "index_ci_builds_on_status", using: :btree
   add_index "ci_builds", ["token"], name: "index_ci_builds_on_token", unique: true, using: :btree
   add_index "ci_builds", ["updated_at"], name: "index_ci_builds_on_updated_at", using: :btree
   add_index "ci_builds", ["user_id"], name: "index_ci_builds_on_user_id", using: :btree