Add Windows unified exec yield floor

codex-rs/core/src/unified_exec/mod.rs

@@ -62,6 +62,7 @@ pub(crate) use process::SpawnLifecycleHandle;
 pub(crate) use process::UnifiedExecProcess;
 
 pub(crate) const MIN_YIELD_TIME_MS: u64 = 250;
+pub(crate) const WINDOWS_INITIAL_EXEC_YIELD_TIME_FLOOR_MS: u64 = 2_000;
 // Minimum yield time for an empty `write_stdin`.
 pub(crate) const MIN_EMPTY_YIELD_TIME_MS: u64 = 5_000;
 pub(crate) const MAX_YIELD_TIME_MS: u64 = 30_000;
@@ -163,6 +164,11 @@ struct ProcessEntry {
 }
 
 pub(crate) fn clamp_yield_time(yield_time_ms: u64) -> u64 {
+    let yield_time_ms = if cfg!(windows) {
+        yield_time_ms.max(WINDOWS_INITIAL_EXEC_YIELD_TIME_FLOOR_MS)
+    } else {
+        yield_time_ms
+    };
     yield_time_ms.clamp(MIN_YIELD_TIME_MS, MAX_YIELD_TIME_MS)
 }
 

codex-rs/core/src/unified_exec/process_manager_tests.rs

@@ -1,4 +1,5 @@
 use super::*;
+use crate::unified_exec::clamp_yield_time;
 use pretty_assertions::assert_eq;
 use tokio::time::Duration;
 use tokio::time::Instant;
@@ -130,6 +131,32 @@ fn exec_server_process_id_matches_unified_exec_process_id() {
     assert_eq!(exec_server_process_id(/*process_id*/ 4321), "4321");
 }
 
+#[cfg(windows)]
+#[test]
+fn initial_exec_yield_time_uses_windows_floor() {
+    let above_max_yield_time_ms = crate::unified_exec::MAX_YIELD_TIME_MS + 1;
+
+    assert_eq!(
+        clamp_yield_time(/*yield_time_ms*/ 1_000),
+        crate::unified_exec::WINDOWS_INITIAL_EXEC_YIELD_TIME_FLOOR_MS
+    );
+    assert_eq!(clamp_yield_time(/*yield_time_ms*/ 10_000), 10_000);
+    assert_eq!(
+        clamp_yield_time(/*yield_time_ms*/ above_max_yield_time_ms),
+        crate::unified_exec::MAX_YIELD_TIME_MS
+    );
+}
+
+#[cfg(not(windows))]
+#[test]
+fn initial_exec_yield_time_has_no_platform_floor() {
+    assert_eq!(clamp_yield_time(/*yield_time_ms*/ 1_000), 1_000);
+    assert_eq!(
+        clamp_yield_time(/*yield_time_ms*/ 1),
+        crate::unified_exec::MIN_YIELD_TIME_MS
+    );
+}
+
 #[tokio::test]
 async fn network_denial_fallback_message_names_sandbox_network_proxy() {
     let message = network_denial_message_for_session(/*session*/ None, /*deferred*/ None).await;