From 3037814fde83d869f7a71567511a6aa5e0700073 Mon Sep 17 00:00:00 2001
From: Roger Braun <roger@rogerbraun.net>
Date: Tue, 31 Oct 2017 15:26:37 +0100
Subject: [PATCH] Only search through last 100_000 activities for fetches.

This is purely a performance enhancement
---
 lib/pleroma/web/activity_pub/activity_pub.ex | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index dcd27d04a..71e52cb46 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -155,6 +155,14 @@ defp restrict_favorited_by(query, %{"favorited_by" => ap_id}) do
   end
   defp restrict_favorited_by(query, _), do: query
 
+  # Only search through last 100_000 activities by default
+  defp restrict_recent(query, _) do
+    since = Repo.aggregate(Activity, :max, :id) - 100_000
+
+    from activity in query,
+      where: activity.id > ^since
+  end
+
   def fetch_activities(recipients, opts \\ %{}) do
     base_query = from activity in Activity,
       limit: 20,
@@ -169,6 +177,7 @@ def fetch_activities(recipients, opts \\ %{}) do
     |> restrict_actor(opts)
     |> restrict_type(opts)
     |> restrict_favorited_by(opts)
+    |> restrict_recent(opts)
     |> Repo.all
     |> Enum.reverse
   end