diff --git a/crates/re_viewer/src/app.rs b/crates/re_viewer/src/app.rs
index d7616968a58d..9701ee2b56c5 100644
--- a/crates/re_viewer/src/app.rs
+++ b/crates/re_viewer/src/app.rs
@@ -750,7 +750,7 @@ impl App {
         &mut self,
         ui: &mut egui::Ui,
         gpu_resource_stats: &WgpuResourcePoolStatistics,
-        store_stats: &StoreHubStats,
+        store_stats: Option<&StoreHubStats>,
     ) {
         let frame = egui::Frame {
             fill: ui.visuals().panel_fill,
@@ -807,7 +807,7 @@ impl App {
         app_blueprint: &AppBlueprint<'_>,
         gpu_resource_stats: &WgpuResourcePoolStatistics,
         store_context: Option<&StoreContext<'_>>,
-        store_stats: &StoreHubStats,
+        store_stats: Option<&StoreHubStats>,
     ) {
         let mut main_panel_frame = egui::Frame::default();
         if re_ui::CUSTOM_WINDOW_DECORATIONS {
@@ -1220,8 +1220,11 @@ impl eframe::App for App {
             }
         }
 
+        // NOTE: GPU resource stats are cheap to compute so we always do.
         // TODO(andreas): store the re_renderer somewhere else.
         let gpu_resource_stats = {
+            re_tracing::profile_scope!("gpu_resource_stats");
+
             let egui_renderer = {
                 let render_state = frame.wgpu_render_state().unwrap();
                 &mut render_state.renderer.read()
@@ -1235,10 +1238,15 @@ impl eframe::App for App {
             render_ctx.gpu_resources.statistics()
         };
 
-        let store_stats = store_hub.stats(self.memory_panel.primary_cache_detailed_stats_enabled());
+        // NOTE: Store and caching stats are very costly to compute: only do so if the memory panel
+        // is opened.
+        let store_stats = self
+            .memory_panel_open
+            .then(|| store_hub.stats(self.memory_panel.primary_cache_detailed_stats_enabled()));
 
         // do early, before doing too many allocations
-        self.memory_panel.update(&gpu_resource_stats, &store_stats);
+        self.memory_panel
+            .update(&gpu_resource_stats, store_stats.as_ref());
 
         self.check_keyboard_shortcuts(egui_ctx);
 
@@ -1276,7 +1284,7 @@ impl eframe::App for App {
             &app_blueprint,
             &gpu_resource_stats,
             store_context.as_ref(),
-            &store_stats,
+            store_stats.as_ref(),
         );
 
         if re_ui::CUSTOM_WINDOW_DECORATIONS {
diff --git a/crates/re_viewer/src/store_hub.rs b/crates/re_viewer/src/store_hub.rs
index 5cb6ff9c6f8b..ca263ed8293c 100644
--- a/crates/re_viewer/src/store_hub.rs
+++ b/crates/re_viewer/src/store_hub.rs
@@ -412,6 +412,8 @@ impl StoreHub {
     // TODO(jleibs): We probably want stats for all recordings, not just
     // the currently selected recording.
     pub fn stats(&self, detailed_cache_stats: bool) -> StoreHubStats {
+        re_tracing::profile_function!();
+
         // If we have an app-id, then use it to look up the blueprint.
         let blueprint = self
             .selected_application_id
diff --git a/crates/re_viewer/src/ui/memory_panel.rs b/crates/re_viewer/src/ui/memory_panel.rs
index 2401bbd9816d..b4fe6692b852 100644
--- a/crates/re_viewer/src/ui/memory_panel.rs
+++ b/crates/re_viewer/src/ui/memory_panel.rs
@@ -28,7 +28,7 @@ impl MemoryPanel {
     pub fn update(
         &mut self,
         gpu_resource_stats: &WgpuResourcePoolStatistics,
-        store_stats: &StoreHubStats,
+        store_stats: Option<&StoreHubStats>,
     ) {
         re_tracing::profile_function!();
         self.history.capture(
@@ -36,9 +36,9 @@ impl MemoryPanel {
                 (gpu_resource_stats.total_buffer_size_in_bytes
                     + gpu_resource_stats.total_texture_size_in_bytes) as _,
             ),
-            Some(store_stats.recording_stats.total.num_bytes as _),
-            Some(store_stats.recording_cached_stats.total_size_bytes() as _),
-            Some(store_stats.blueprint_stats.total.num_bytes as _),
+            store_stats.map(|stats| stats.recording_stats.total.num_bytes as _),
+            store_stats.map(|stats| stats.recording_cached_stats.total_size_bytes() as _),
+            store_stats.map(|stats| stats.blueprint_stats.total.num_bytes as _),
         );
     }
 
@@ -61,7 +61,7 @@ impl MemoryPanel {
         re_ui: &re_ui::ReUi,
         limit: &MemoryLimit,
         gpu_resource_stats: &WgpuResourcePoolStatistics,
-        store_stats: &StoreHubStats,
+        store_stats: Option<&StoreHubStats>,
     ) {
         re_tracing::profile_function!();
 
@@ -88,7 +88,7 @@ impl MemoryPanel {
         re_ui: &re_ui::ReUi,
         limit: &MemoryLimit,
         gpu_resource_stats: &WgpuResourcePoolStatistics,
-        store_stats: &StoreHubStats,
+        store_stats: Option<&StoreHubStats>,
     ) {
         ui.strong("Rerun Viewer resource usage");
 
@@ -102,28 +102,30 @@ impl MemoryPanel {
             Self::gpu_stats(ui, gpu_resource_stats);
         });
 
-        ui.separator();
-        ui.collapsing("Datastore Resources", |ui| {
-            Self::store_stats(
-                ui,
-                &store_stats.recording_config,
-                &store_stats.recording_stats,
-            );
-        });
+        if let Some(store_stats) = store_stats {
+            ui.separator();
+            ui.collapsing("Datastore Resources", |ui| {
+                Self::store_stats(
+                    ui,
+                    &store_stats.recording_config,
+                    &store_stats.recording_stats,
+                );
+            });
 
-        ui.separator();
-        ui.collapsing("Primary Cache Resources", |ui| {
-            self.caches_stats(ui, re_ui, &store_stats.recording_cached_stats);
-        });
+            ui.separator();
+            ui.collapsing("Primary Cache Resources", |ui| {
+                self.caches_stats(ui, re_ui, &store_stats.recording_cached_stats);
+            });
 
-        ui.separator();
-        ui.collapsing("Blueprint Resources", |ui| {
-            Self::store_stats(
-                ui,
-                &store_stats.blueprint_config,
-                &store_stats.blueprint_stats,
-            );
-        });
+            ui.separator();
+            ui.collapsing("Blueprint Resources", |ui| {
+                Self::store_stats(
+                    ui,
+                    &store_stats.blueprint_config,
+                    &store_stats.blueprint_stats,
+                );
+            });
+        }
     }
 
     fn cpu_stats(ui: &mut egui::Ui, re_ui: &re_ui::ReUi, limit: &MemoryLimit) {