diff --git a/src/pretix/control/forms/orders.py b/src/pretix/control/forms/orders.py
index 6c5e8b40a1..fe7398333b 100644
--- a/src/pretix/control/forms/orders.py
+++ b/src/pretix/control/forms/orders.py
@@ -562,9 +562,7 @@ class OrderPositionChangeForm(forms.Form):
         if instance.addon_to_id:
             del self.fields['operation_split']
 
-        if not instance.seat and not (
-                instance.item.seat_category_mappings.filter(subevent=instance.subevent).exists()
-        ):
+        if not instance.seat and not instance._seat_allowed:
             del self.fields['seat']
 
         choices = [
diff --git a/src/pretix/control/logdisplay.py b/src/pretix/control/logdisplay.py
index 1204fcc834..60d44f50a2 100644
--- a/src/pretix/control/logdisplay.py
+++ b/src/pretix/control/logdisplay.py
@@ -33,6 +33,7 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
 
+import functools
 from collections import defaultdict
 from datetime import datetime
 from decimal import Decimal
@@ -69,6 +70,15 @@ OVERVIEW_BANLIST = [
 ]
 
 
+@functools.lru_cache(maxsize=32)
+def object_id_to_string(model_class, **kwargs):
+    # The cache is thread-local and persists requests, but it's small enough that we can accept that
+    try:
+        return str(model_class.objects.get(**kwargs))
+    except model_class.DoesNotExist:
+        return "?"
+
+
 class OrderChangeLogEntryType(OrderLogEntryType):
     prefix = _('The order has been changed:')
 
@@ -93,10 +103,10 @@ class OrderItemChanged(OrderChangeLogEntryType):
     def display_prefixed(self, event: Event, logentry: LogEntry, data):
         old_item = str(event.items.get(pk=data['old_item']))
         if data['old_variation']:
-            old_item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['old_variation']))
+            old_item += ' - ' + str(object_id_to_string(ItemVariation, item__event_id=event.pk, pk=data['old_variation']))
         new_item = str(event.items.get(pk=data['new_item']))
         if data['new_variation']:
-            new_item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['new_variation']))
+            new_item += ' - ' + str(object_id_to_string(ItemVariation, item__event_id=event.pk, pk=data['new_variation']))
         return _('Position #{posid}: {old_item} ({old_price}) changed to {new_item} ({new_price}).').format(
             posid=data.get('positionid', '?'),
             old_item=old_item, new_item=new_item,
@@ -153,14 +163,14 @@ class OrderTaxRuleChanged(OrderChangeLogEntryType):
         if 'positionid' in data:
             return _('Tax rule of position #{posid} changed from {old_rule} to {new_rule}.').format(
                 posid=data.get('positionid', '?'),
-                old_rule=TaxRule.objects.get(pk=data['old_taxrule']) if data['old_taxrule'] else '–',
-                new_rule=TaxRule.objects.get(pk=data['new_taxrule']),
+                old_rule=object_id_to_string(TaxRule, pk=data['old_taxrule']) if data['old_taxrule'] else '–',
+                new_rule=object_id_to_string(TaxRule, pk=data['new_taxrule']),
             )
         elif 'fee' in data:
             return _('Tax rule of fee #{fee} changed from {old_rule} to {new_rule}.').format(
                 fee=data.get('fee', '?'),
-                old_rule=TaxRule.objects.get(pk=data['old_taxrule']) if data['old_taxrule'] else '–',
-                new_rule=TaxRule.objects.get(pk=data['new_taxrule']),
+                old_rule=object_id_to_string(TaxRule, pk=data['old_taxrule']) if data['old_taxrule'] else '–',
+                new_rule=object_id_to_string(TaxRule, pk=data['new_taxrule']),
             )
 
 
@@ -204,7 +214,7 @@ class OrderCanceled(OrderChangeLogEntryType):
     def display_prefixed(self, event: Event, logentry: LogEntry, data):
         old_item = str(event.items.get(pk=data['old_item']))
         if data['old_variation']:
-            old_item += ' - ' + str(ItemVariation.objects.get(pk=data['old_variation']))
+            old_item += ' - ' + object_id_to_string(ItemVariation, pk=data['old_variation'])
         return _('Position #{posid} ({old_item}, {old_price}) canceled.').format(
             posid=data.get('positionid', '?'),
             old_item=old_item,
@@ -219,7 +229,7 @@ class OrderPositionAdded(OrderChangeLogEntryType):
     def display_prefixed(self, event: Event, logentry: LogEntry, data):
         item = str(event.items.get(pk=data['item']))
         if data['variation']:
-            item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['variation']))
+            item += ' - ' + object_id_to_string(ItemVariation, item__event_id=event.pk, pk=data['variation'])
         if data['addon_to']:
             addon_to = OrderPosition.objects.get(order__event=event, pk=data['addon_to'])
             return _('Position #{posid} created: {item} ({price}) as an add-on to position #{addon_to}.').format(
@@ -283,7 +293,7 @@ class OrderChangedSplit(OrderChangeLogEntryType):
     def display_prefixed(self, event: Event, logentry: LogEntry, data):
         old_item = str(event.items.get(pk=data['old_item']))
         if data['old_variation']:
-            old_item += ' - ' + str(ItemVariation.objects.get(pk=data['old_variation']))
+            old_item += ' - ' + object_id_to_string(ItemVariation, pk=data['old_variation'])
         url = reverse('control:event.order', kwargs={
             'event': event.slug,
             'organizer': event.organizer.slug,
@@ -339,6 +349,7 @@ class OrderChangedSplitFrom(OrderLogEntryType):
     'pretix.event.checkin.reverted': _('The check-in of position #{posid} on list "{list}" has been reverted.'),
 })
 class CheckinErrorLogEntryType(OrderLogEntryType):
+
     def display(self, logentry: LogEntry, data):
         return self.display_plain(self.plain, logentry, data)
 
@@ -353,10 +364,7 @@ class CheckinErrorLogEntryType(OrderLogEntryType):
         event = logentry.event
 
         if 'list' in data and event:
-            try:
-                data['list'] = event.checkin_lists.get(pk=data.get('list')).name
-            except CheckinList.DoesNotExist:
-                data['list'] = _("(unknown)")
+            data['list'] = object_id_to_string(CheckinList, event_id=event.id, pk=data['list'])
         else:
             data['list'] = _("(unknown)")
 
diff --git a/src/pretix/control/templates/pretixcontrol/order/index.html b/src/pretix/control/templates/pretixcontrol/order/index.html
index cdba94c04b..88276398e3 100644
--- a/src/pretix/control/templates/pretixcontrol/order/index.html
+++ b/src/pretix/control/templates/pretixcontrol/order/index.html
@@ -833,7 +833,7 @@
                                 <strong>{% trans "Pending total" %}</strong>
                             </div>
                             <div class="col-md-3 col-xs-6 col-md-offset-5 price">
-                                <strong>{{ order.pending_sum|money:event.currency }}</strong>
+                                <strong>{{ pending_sum|money:event.currency }}</strong>
                             </div>
                             <div class="clearfix"></div>
                         </div>
diff --git a/src/pretix/control/views/orders.py b/src/pretix/control/views/orders.py
index 8245d78ed8..e1c19c549c 100644
--- a/src/pretix/control/views/orders.py
+++ b/src/pretix/control/views/orders.py
@@ -81,7 +81,7 @@ from pretix.base.i18n import language
 from pretix.base.models import (
     CachedFile, CachedTicket, Checkin, GiftCard, Invoice, InvoiceAddress, Item,
     ItemVariation, LogEntry, Order, QuestionAnswer, Quota,
-    ScheduledEventExport, generate_secret,
+    ScheduledEventExport, SeatCategoryMapping, generate_secret,
 )
 from pretix.base.models.orders import (
     CancellationRequest, OrderFee, OrderPayment, OrderPosition, OrderRefund,
@@ -564,10 +564,11 @@ class OrderDetail(OrderView):
         })
         ctx['display_locale'] = dict(settings.LANGUAGES)[self.object.locale or self.request.event.settings.locale]
 
-        ctx['overpaid'] = self.order.pending_sum * -1
+        pending_sum = self.order.pending_sum
+        ctx['overpaid'] = pending_sum * -1
         ctx['download_buttons'] = self.download_buttons
         ctx['payment_refund_sum'] = self.order.payment_refund_sum
-        ctx['pending_sum'] = self.order.pending_sum
+        ctx['pending_sum'] = pending_sum
         ctx['uncancelled_invoice'] = self.order.invoices.exclude(
             Exists(self.order.invoices.filter(refers=OuterRef('pk'), is_cancellation=True))
         ).exclude(is_cancellation=True).first()
@@ -601,8 +602,9 @@ class OrderDetail(OrderView):
         ).prefetch_related(
             'item__questions', 'issued_gift_cards', 'owned_gift_cards', 'linked_media',
             Prefetch('answers', queryset=QuestionAnswer.objects.prefetch_related('options').select_related('question')),
-            Prefetch('all_checkins', queryset=Checkin.all.select_related('list').order_by('datetime')),
+            Prefetch('all_checkins', queryset=Checkin.all.select_related('list', 'gate').order_by('datetime')),
             Prefetch('print_logs', queryset=PrintLog.objects.select_related('device').order_by('datetime')),
+            Prefetch('subevent', queryset=self.request.event.subevents.all()),
         ).order_by('positionid')
 
         positions = []
@@ -1985,20 +1987,37 @@ class OrderChange(OrderView):
     def fees(self):
         fees = list(self.order.fees.all())
         for f in fees:
-            f.form = OrderFeeChangeForm(prefix='of-{}'.format(f.pk), instance=f,
-                                        data=self.request.POST if self.request.method == "POST" else None)
+            f.form = OrderFeeChangeForm(
+                prefix='of-{}'.format(f.pk),
+                instance=f,
+                data=self.request.POST if self.request.method == "POST" else None
+            )
         return fees
 
     @cached_property
     def positions(self):
         positions = list(self.order.positions.select_related(
             'item', 'item__tax_rule', 'used_membership', 'used_membership__membership_type', 'tax_rule',
-            'seat', 'subevent',
-        ).prefetch_related('granted_memberships', 'issued_gift_cards'))
+            'seat',
+        ).prefetch_related(
+            Prefetch(
+                'subevent',
+                queryset=self.request.event.subevents.all(),
+            ),
+            'granted_memberships',
+            'issued_gift_cards',
+            'addons',
+        ).annotate(
+            _seat_allowed=Exists(SeatCategoryMapping.objects.filter(subevent=OuterRef("subevent"), product=OuterRef("item")))
+        ))
         for p in positions:
-            p.form = OrderPositionChangeForm(prefix='op-{}'.format(p.pk), instance=p, items=self.items,
-                                             initial={'seat': p.seat.seat_guid if p.seat else None},
-                                             data=self.request.POST if self.request.method == "POST" else None)
+            p.form = OrderPositionChangeForm(
+                prefix='op-{}'.format(p.pk),
+                instance=p,
+                items=self.items,
+                initial={'seat': p.seat.seat_guid if p.seat else None},
+                data=self.request.POST if self.request.method == "POST" else None
+            )
         return positions
 
     def get_context_data(self, **kwargs):