diff --git a/codex-rs/app-server/src/message_processor_tracing_tests.rs b/codex-rs/app-server/src/message_processor_tracing_tests.rs
index b8e59cb2b7..55875c81f6 100644
--- a/codex-rs/app-server/src/message_processor_tracing_tests.rs
+++ b/codex-rs/app-server/src/message_processor_tracing_tests.rs
@@ -276,7 +276,7 @@ fn run_current_thread_test_with_stack<F>(name: &str, future: F) -> Result<()>
 where
     F: Future<Output = Result<()>> + Send + 'static,
 {
-    const TEST_STACK_SIZE_BYTES: usize = 4 * 1024 * 1024;
+    const TEST_STACK_SIZE_BYTES: usize = 8 * 1024 * 1024;
 
     let handle = std::thread::Builder::new()
         .name(name.to_string())