1 files changed, 36 insertions, 0 deletions
diff --git a/db/post_migrate/20230104150601_prepare_builds_metadata_async_idx.rb b/db/post_migrate/20230104150601_prepare_builds_metadata_async_idx.rb
new file mode 100644
index 00000000000..83dfe62ad71
--- /dev/null
+++ b/db/post_migrate/20230104150601_prepare_builds_metadata_async_idx.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+class PrepareBuildsMetadataAsyncIdx < Gitlab::Database::Migration[2.1]
+  include Gitlab::Database::PartitioningMigrationHelpers
+
+  disable_ddl_transaction!
+
+  INDEX_NAME = 'p_ci_builds_metadata_on_runner_machine_id_idx'
+
+  def up
+    # Break up the logic from add_concurrent_partitioned_index so that the partition indices can be created async
+    # A follow-up migration will complete the index creation by creating the index on the metadata table, and
+    # creating the concurrent foreign key
+    each_partition(:p_ci_builds_metadata) do |partition, partition_index_name|
+      prepare_async_index(partition.identifier, :runner_machine_id,
+                          name: partition_index_name, where: 'runner_machine_id IS NOT NULL')
+    end
+  end
+
+  def down
+    each_partition(:p_ci_builds_metadata) do |partition, partition_index_name|
+      unprepare_async_index_by_name(partition.identifier, partition_index_name)
+    end
+  end
+
+  private
+
+  def each_partition(table_name)
+    partitioned_table = find_partitioned_table(table_name)
+    partitioned_table.postgres_partitions.order(:name).each do |partition|
+      partition_index_name = generated_index_name(partition.identifier, INDEX_NAME)
+
+      yield partition, partition_index_name
+    end
+  end
+end