From 22204b49dd4f27deb51be111c48478a86c5de58f Mon Sep 17 00:00:00 2001
From: cy <cy@cy7.sh>
Date: Fri, 14 Mar 2025 13:19:36 -0400
Subject: [PATCH] patch attic to prefetch 32 chunks instead of 2

---
 overlay/attic/default.nix              |  7 +++++++
 overlay/attic/prefetch-32-chunks.patch | 13 +++++++++++++
 overlay/default.nix                    |  1 +
 3 files changed, 21 insertions(+)
 create mode 100644 overlay/attic/default.nix
 create mode 100644 overlay/attic/prefetch-32-chunks.patch

diff --git a/overlay/attic/default.nix b/overlay/attic/default.nix
new file mode 100644
index 0000000..14f5daf
--- /dev/null
+++ b/overlay/attic/default.nix
@@ -0,0 +1,7 @@
+final: prev: {
+  attic-server = prev.attic-server.overrideAttrs {
+    patches = [
+      ./prefetch-32-chunks.patch
+    ];
+  };
+}
diff --git a/overlay/attic/prefetch-32-chunks.patch b/overlay/attic/prefetch-32-chunks.patch
new file mode 100644
index 0000000..bbb801b
--- /dev/null
+++ b/overlay/attic/prefetch-32-chunks.patch
@@ -0,0 +1,13 @@
+diff --git a/server/src/api/binary_cache.rs b/server/src/api/binary_cache.rs
+index 02e4857..71eeee8 100644
+--- a/server/src/api/binary_cache.rs
++++ b/server/src/api/binary_cache.rs
+@@ -262,7 +262,7 @@ async fn get_nar(
+ 
+         // TODO: Make num_prefetch configurable
+         // The ideal size depends on the average chunk size
+-        let merged = merge_chunks(chunks, streamer, storage, 2).map_err(|e| {
++        let merged = merge_chunks(chunks, streamer, storage, 32).map_err(|e| {
+             tracing::error!(%e, "Stream error");
+             e
+         });
diff --git a/overlay/default.nix b/overlay/default.nix
index 3a655fd..0eea626 100644
--- a/overlay/default.nix
+++ b/overlay/default.nix
@@ -3,6 +3,7 @@ let
   overlays = [
     ./zipline
     ./bitwarden
+    ./attic
   ];
   importedOverlays = map (m: import m) overlays;
 in