I have the following resource in my system:

defmodule Pacman.Markets.Record do
  @moduledoc false

  use Ash.Resource,
    data_layer: AshPostgres.DataLayer,
    extensions: [UUIDV7]

  attributes do
    uuid_v7_primary_key :id, writable?: true

    timestamps(private?: false)
  end

  relationships do
    alias Pacman.Markets.Entity

    belongs_to :grantee_entity, Entity do
      allow_nil? true
      attribute_writable? true

      destination_attribute :id
    end
  end

  postgres do
    table "records"

    repo Pacman.Repo
  end
end

In my Entityresource, I have the following action:

read :all_stale do
      filter expr(status == :stale)

      prepare build(limit: 1000)
    end

And relationship:

    has_many :grantee_records, Record do
      destination_attribute :grantee_entity_id
    end

Now I’m trying to run that action and load the grantee_records relationship:

iex(1)> Pacman.Markets.Entity.all_stale() |> Pacman.Markets.load!(:grantee_records)
[debug] QUERY OK source="entities" db=6.9ms queue=0.7ms idle=1283.2ms
SELECT e0."id", e0."first_name", e0."middle_name", e0."last_name", e0."name_suffix", e0."full_name", e0."address_house_number", e0."address_street_direction", e0."address_street_name", e0."address_street_suffix", e0."address_street_post_direction", e0."address_unit_prefix", e0."address_unit_value", e0."address_city", e0."address_state", e0."address_zip", e0."address_zip_4", e0."address_legacy", e0."address_normalized", e0."address", e0."status", e0."total_records", e0."total_buy_records", e0."total_sell_records", e0."fix_and_flip?", e0."buy_and_hold?", e0."wholesaler?", e0."year_before_last", e0."year_before_last_buy_records", e0."year_before_last_buy_transfer_amount", e0."year_before_last_sell_records", e0."year_before_last_sell_transfer_amount", e0."last_year", e0."last_year_buy_records", e0."last_year_buy_transfer_amount", e0."last_year_sell_records", e0."last_year_sell_transfer_amount", e0."current_year", e0."current_year_buy_records", e0."current_year_buy_transfer_amount", e0."current_year_sell_records", e0."current_year_sell_transfer_amount", e0."score", e0."score_version", e0."inserted_at", e0."updated_at" FROM "entities" AS e0 WHERE (e0."status"::varchar = $1::varchar) LIMIT $2 [:stale, 1000]
[debug] QUERY OK source="records" db=44.2ms decode=0.1ms queue=4.2ms idle=1441.2ms
SELECT r0."id", r0."inserted_at", r0."updated_at", r0."grantee_entity_id", r0."grantor_entity_id" FROM "records" AS r0 WHERE (r0."grantee_entity_id"::uuid IN 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As you can see from the logs, the action and load queries run pretty fast (6.9ms, 44.2ms), but after the load query runs, it will take around 1~5 minutes for the Pacman.Markets.load! call to return the values, and during that time the erlang VM will be at 100% CPU.

I tested it both the ash and ash_postgres using main and latest version.