diff --git a/Cargo.lock b/Cargo.lock
index 4b058ef..b44d326 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -995,7 +995,7 @@ dependencies = [
 
 [[package]]
 name = "pict-rs"
-version = "0.3.0-alpha.13"
+version = "0.3.0-alpha.15"
 dependencies = [
  "actix-form-data",
  "actix-fs",
diff --git a/Cargo.toml b/Cargo.toml
index c8a2c7b..f782aa7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "pict-rs"
 description = "A simple image hosting service"
-version = "0.3.0-alpha.13"
+version = "0.3.0-alpha.15"
 authors = ["asonix <asonix@asonix.dog>"]
 license = "AGPL-3.0"
 readme = "README.md"
diff --git a/docker/prod/docker-compose.yml b/docker/prod/docker-compose.yml
index 5d95a69..8c3315b 100644
--- a/docker/prod/docker-compose.yml
+++ b/docker/prod/docker-compose.yml
@@ -2,7 +2,7 @@ version: '3.3'
 
 services:
   pictrs:
-    image: asonix/pictrs:v0.3.0-alpha.14
+    image: asonix/pictrs:v0.3.0-alpha.15
     ports:
       - "127.0.0.1:8080:8080"
     restart: always
diff --git a/src/exiv2.rs b/src/exiv2.rs
index 60fdee7..59be3b7 100644
--- a/src/exiv2.rs
+++ b/src/exiv2.rs
@@ -14,7 +14,7 @@ static MAX_READS: once_cell::sync::OnceCell<tokio::sync::Semaphore> =
     once_cell::sync::OnceCell::new();
 
 fn semaphore() -> &'static tokio::sync::Semaphore {
-    MAX_READS.get_or_init(|| tokio::sync::Semaphore::new(num_cpus::get() * 4))
+    MAX_READS.get_or_init(|| tokio::sync::Semaphore::new(num_cpus::get() * 5))
 }
 
 pub(crate) async fn clear_metadata<P>(file: P) -> Result<(), Exvi2Error>
diff --git a/src/magick.rs b/src/magick.rs
index e5c7d14..4f239c4 100644
--- a/src/magick.rs
+++ b/src/magick.rs
@@ -31,8 +31,7 @@ static MAX_CONVERSIONS: once_cell::sync::OnceCell<tokio::sync::Semaphore> =
     once_cell::sync::OnceCell::new();
 
 fn semaphore() -> &'static tokio::sync::Semaphore {
-    MAX_CONVERSIONS
-        .get_or_init(|| tokio::sync::Semaphore::new(num_cpus::get().saturating_sub(1).max(1)))
+    MAX_CONVERSIONS.get_or_init(|| tokio::sync::Semaphore::new(num_cpus::get().max(1) * 5))
 }
 
 pub(crate) async fn convert_file<P1, P2>(