From 3d888d7b070043cefbc442b257825f4a948f7d2a Mon Sep 17 00:00:00 2001
From: MikaAK <mika@kalathil.me>
Date: Sun, 3 May 2026 19:10:29 -0700
Subject: [PATCH 1/2] perf(sandbox): make register_caches sleep configurable

Cache.SandboxRegistry.register_caches/2 sleeps Process.sleep(50) after
each Registry.register call to give the entry time to propagate. With N
caches registered per test (common in apps with many cache modules),
this becomes ~N * 50ms of fixed overhead per test setup.

Read the value via Application.compile_env(:elixir_cache,
:sandbox_sleep_ms, 50). Default is unchanged at 50ms (backward
compatible). Test suites can opt in to a faster value (commonly 0):

    # config/test.exs
    config :elixir_cache, :sandbox_sleep_ms, 0

In a downstream umbrella with several cache apps, setting this to 0
saved ~1.7s across last_symbol_price_cache (10 tests x 102ms),
open_interest_cache (10 x 51ms), options_contract_expiry_cache
(3 x 51ms), and active_symbols_cache (4 x 51ms).
---
 CHANGELOG.md                  | 6 ++++++
 lib/cache/sandbox_registry.ex | 2 +-
 mix.exs                       | 2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4ee6cbb..fbd222a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# 0.4.9
+
+## Performance
+
+- perf(sandbox): make `Cache.SandboxRegistry.register_caches/2` post-register sleep configurable via `Application.compile_env(:elixir_cache, :sandbox_sleep_ms, 50)`. Default is unchanged (50 ms). Test suites that don't need the sleep can set it to 0 to save ~50 ms per cache registered per test — material on apps with many cache modules.
+
 # 0.4.8
 
 ## Bug Fixes
diff --git a/lib/cache/sandbox_registry.ex b/lib/cache/sandbox_registry.ex
index fe57f29..95a09d7 100644
--- a/lib/cache/sandbox_registry.ex
+++ b/lib/cache/sandbox_registry.ex
@@ -5,7 +5,7 @@ defmodule Cache.SandboxRegistry do
   More details soon...
   """
 
-  @sleep_for_sync 50
+  @sleep_for_sync Application.compile_env(:elixir_cache, :sandbox_sleep_ms, 50)
   @registry :elixir_cache_sandbox
   @keys :duplicate
 
diff --git a/mix.exs b/mix.exs
index 618d38e..6f638d0 100644
--- a/mix.exs
+++ b/mix.exs
@@ -4,7 +4,7 @@ defmodule ElixirCache.MixProject do
   def project do
     [
       app: :elixir_cache,
-      version: "0.4.8",
+      version: "0.4.9",
       elixir: "~> 1.11",
       start_permanent: Mix.env() == :prod,
       description:

From 97183c2d41a206f969117840cd73f5e5f40b989c Mon Sep 17 00:00:00 2001
From: MikaAK <mika@kalathil.me>
Date: Sun, 3 May 2026 19:25:20 -0700
Subject: [PATCH 2/2] refactor: route sandbox_sleep_ms through Cache.Config
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Per the request_cache_plug Config module pattern. Adds
lib/cache/config.ex with `Cache.Config.sandbox_sleep_ms/0` and switches
SandboxRegistry from a compile-time module attribute reading
Application.compile_env to a runtime call to the accessor.

Two reasons the runtime form is better here:
  1. Process.sleep is already runtime-bound; the extra Application.get_env
     call is a no-op compared to the actual sleep.
  2. Future config knobs (TTL defaults, log levels, etc.) can land on the
     same module, making the contract for downstream apps obvious — they
     `config :elixir_cache, ...` and read via `Cache.Config`.

No behavior change vs. the previous commit on this branch — default
still 50 ms, override via the same `config :elixir_cache,
:sandbox_sleep_ms, N` key.
---
 CHANGELOG.md                  | 2 +-
 lib/cache/config.ex           | 9 +++++++++
 lib/cache/sandbox_registry.ex | 3 +--
 3 files changed, 11 insertions(+), 3 deletions(-)
 create mode 100644 lib/cache/config.ex

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fbd222a..51ffc2d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 ## Performance
 
-- perf(sandbox): make `Cache.SandboxRegistry.register_caches/2` post-register sleep configurable via `Application.compile_env(:elixir_cache, :sandbox_sleep_ms, 50)`. Default is unchanged (50 ms). Test suites that don't need the sleep can set it to 0 to save ~50 ms per cache registered per test — material on apps with many cache modules.
+- perf(sandbox): make `Cache.SandboxRegistry.register_caches/2` post-register sleep configurable via `Cache.Config.sandbox_sleep_ms/0` (`config :elixir_cache, :sandbox_sleep_ms, 50`). Default is unchanged (50 ms). Test suites that don't need the sleep can set it to `0` in `config/test.exs` to save ~50 ms per cache registered per test — material on apps with many cache modules.
 
 # 0.4.8
 
diff --git a/lib/cache/config.ex b/lib/cache/config.ex
new file mode 100644
index 0000000..c73c30a
--- /dev/null
+++ b/lib/cache/config.ex
@@ -0,0 +1,9 @@
+defmodule Cache.Config do
+  @moduledoc false
+
+  @app :elixir_cache
+
+  def sandbox_sleep_ms do
+    Application.get_env(@app, :sandbox_sleep_ms, 50)
+  end
+end
diff --git a/lib/cache/sandbox_registry.ex b/lib/cache/sandbox_registry.ex
index 95a09d7..5674213 100644
--- a/lib/cache/sandbox_registry.ex
+++ b/lib/cache/sandbox_registry.ex
@@ -5,7 +5,6 @@ defmodule Cache.SandboxRegistry do
   More details soon...
   """
 
-  @sleep_for_sync Application.compile_env(:elixir_cache, :sandbox_sleep_ms, 50)
   @registry :elixir_cache_sandbox
   @keys :duplicate
 
@@ -38,7 +37,7 @@ defmodule Cache.SandboxRegistry do
         {:error, :registry_not_started} -> raise_not_started!()
       end
 
-    Process.sleep(@sleep_for_sync)
+    Process.sleep(Cache.Config.sandbox_sleep_ms())
 
     res
   end