perf: eliminate N+1 queries on queues index

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Slow job webhook alert — set `alert_slow_job_count_threshold` (integer) to fire a webhook whenever the number of currently-running slow jobs meets or exceeds the configured count; requires `slow_job_threshold` to define what "slow" means; uses the same `alert_webhook_url` and `alert_webhook_cooldown` settings as other alert types; event name `slow_job_threshold_exceeded`
 - Stale process webhook alert — set `alert_stale_process_threshold` (integer) to fire a webhook whenever the number of stale workers meets or exceeds the configured count; a process is stale when its heartbeat has not been updated within `SolidQueue.process_alive_threshold`; uses the same `alert_webhook_url` and `alert_webhook_cooldown` settings; event name `stale_process_detected`
 - Job wait time column — the Running tab now shows a "Wait Time" column displaying how long each claimed job waited in the queue from enqueue to pickup; also included as `wait_time_seconds` in the CSV export for the claimed status
+- Eliminate N+1 queries on the queues index — `queue.size` and `queue.paused?` previously fired one query each per queue; both are now pre-computed in the controller with single batch aggregations (`GROUP BY queue_name` for sizes, one `Pause` query for paused state), reducing query count from O(2N+constant) to O(constant) regardless of queue count
 
 ## [1.3.0] - 2026-05-27
 

ROADMAP.md

@@ -17,7 +17,7 @@ Pull requests for any of these are welcome. See [Contributing](README.md#contrib
 | ~~**Slow job webhook alert**~~ | ✅ Shipped in v1.4 — `alert_slow_job_count_threshold` fires when slow-job count meets or exceeds the threshold. |
 | ~~**Process stale webhook alert**~~ | ✅ Shipped in v1.4 — `alert_stale_process_threshold` fires when stale worker count meets or exceeds the threshold. |
 | ~~**Job wait time column**~~ | ✅ Shipped in v1.4 — "Wait Time" column on the Running tab; `wait_time_seconds` in the claimed CSV export. |
-| **Eliminate N+1 queries** | Queues index fires 2 extra queries per queue: `queue.size` (COUNT per queue) and `queue.paused?` (EXISTS per queue). Replace with single batch aggregations pre-computed in the controller. |
+| ~~**Eliminate N+1 queries**~~ | ✅ Shipped in v1.4 — queue size and paused state now pre-computed with single batch aggregations; query count reduced from O(2N) to O(1) per page load. |
 
 ---
 

app/controllers/solid_queue_web/queues_controller.rb

@@ -7,6 +7,11 @@ def index
       @failed_24h         = stats.failed_24h
       @oldest_ready       = stats.oldest_ready
       @failure_sparklines = stats.failure_sparklines
+      @queue_sizes        = SolidQueue::ReadyExecution
+        .joins(:job)
+        .group("solid_queue_jobs.queue_name")
+        .count
+      @paused_queue_names = SolidQueue::Pause.pluck(:queue_name).to_set
     end
   end
 end

app/views/solid_queue_web/queues/index.html.erb

@@ -21,7 +21,7 @@
         <% @queues.each do |queue| %>
           <tr>
             <td class="sqd-mono"><%= queue.name %></td>
-            <td><%= queue.size %></td>
+            <td><%= @queue_sizes[queue.name] || 0 %></td>
             <td>
               <% if (oldest = @oldest_ready[queue.name]) %>
                 <% age = Time.current - oldest %>
@@ -52,14 +52,14 @@
               <% end %>
             </td>
             <td>
-              <% if queue.paused? %>
+              <% if @paused_queue_names.include?(queue.name) %>
                 <span class="sqd-badge sqd-badge--paused">Paused</span>
               <% else %>
                 <span class="sqd-badge sqd-badge--running">Running</span>
               <% end %>
             </td>
             <td class="sqd-row-actions">
-              <% if queue.paused? %>
+              <% if @paused_queue_names.include?(queue.name) %>
                 <%= button_to "Resume", queue_pause_path(queue.name), method: :delete,
                       class: "sqd-btn sqd-btn--primary sqd-btn--sm" %>
               <% else %>

spec/requests/solid_queue_web/queues_spec.rb

@@ -68,6 +68,48 @@
     end
   end
 
+  describe "GET /jobs/queues — batch-loaded queue size and paused state" do
+    it "shows the ready job count for a queue" do
+      job = SolidQueue::Job.create!(
+        queue_name: "default", class_name: "TestJob",
+        arguments: {}, active_job_id: SecureRandom.uuid
+      )
+      job.ready_execution
+      get "/jobs/queues"
+      expect(response.body).to match(/<td>\s*\d+\s*<\/td>/)
+    end
+
+    it "shows 0 size for a queue with no ready jobs" do
+      SolidQueue::ReadyExecution.delete_all
+      get "/jobs/queues"
+      expect(response.body).to include("<td>0</td>")
+    end
+
+    it "shows the Paused badge for a paused queue" do
+      SolidQueue::Pause.create!(queue_name: "default")
+      get "/jobs/queues"
+      expect(response.body).to include("sqd-badge--paused")
+      expect(response.body).to include("Paused")
+    end
+
+    it "shows the Running badge for an unpaused queue" do
+      get "/jobs/queues"
+      expect(response.body).to include("sqd-badge--running")
+      expect(response.body).to include("Running")
+    end
+
+    it "shows Resume button for a paused queue" do
+      SolidQueue::Pause.create!(queue_name: "default")
+      get "/jobs/queues"
+      expect(response.body).to include("Resume")
+    end
+
+    it "shows Pause button for a running queue" do
+      get "/jobs/queues"
+      expect(response.body).to include("Pause")
+    end
+  end
+
   describe "POST /jobs/queues/:name/pause" do
     it "pauses the queue and redirects" do
       post "/jobs/queues/default/pause"