diff --git a/Cargo.lock b/Cargo.lock
index 6d5ee309..aa30bdc8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1160,7 +1160,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_builtins"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "chrono",
  "fast-float",
@@ -1185,7 +1185,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_bytecode"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "num-bigint",
  "oxide_log",
@@ -1193,7 +1193,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_cfg"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_emit",
@@ -1204,7 +1204,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_cli"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "ansi_term",
  "bumpalo",
@@ -1225,7 +1225,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_code_cache"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "lru",
  "oxide_bytecode",
@@ -1234,7 +1234,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_compiler"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1253,7 +1253,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_dce"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1267,7 +1267,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_emit"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "num-bigint",
  "oxc_allocator",
@@ -1282,7 +1282,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_ir"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_log",
@@ -1291,7 +1291,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_kernel"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "bumpalo",
  "dashmap",
@@ -1306,7 +1306,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_liveness"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1318,7 +1318,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_log"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "tracing",
  "tracing-appender",
@@ -1327,7 +1327,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_parser"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxc_allocator",
  "oxc_ast",
@@ -1342,7 +1342,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_regalloc"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_cfg",
@@ -1358,7 +1358,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_runtime_api"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "num-bigint",
  "num-traits",
@@ -1370,7 +1370,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_test262"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "oxide_bytecode",
  "oxide_compiler",
@@ -1387,7 +1387,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_types"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "bumpalo",
  "hashbrown 0.14.5",
@@ -1399,7 +1399,7 @@ dependencies = [
 
 [[package]]
 name = "oxide_vm"
-version = "0.8.43"
+version = "0.8.44"
 dependencies = [
  "bumpalo",
  "chrono",
diff --git a/Cargo.toml b/Cargo.toml
index 39770b70..3498fe98 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.8.43"
+version = "0.8.44"
 edition = "2021"
 license = "MIT"
 rust-version = "1.80"
diff --git a/crates/oxide_vm/src/vm/dispatch_loop.rs b/crates/oxide_vm/src/vm/dispatch_loop.rs
index b3839ba2..c94689a5 100644
--- a/crates/oxide_vm/src/vm/dispatch_loop.rs
+++ b/crates/oxide_vm/src/vm/dispatch_loop.rs
@@ -125,9 +125,10 @@ impl Vm {
             // 返回顶层后检查恢复，存活值此时已回拷为执行根。账目未超水位时仅
             // 少量字段比较。
             if self.native_call_depth == 0 {
-                // 宿主 `$262.gc()` 置位的强制收集在此边界消费：完整收集
-                // 唯一安全点（无在途 dispatch 局部值），与正常触发路径同一入口。
-                if self.gc_state.pending_forced_collect {
+                // 宿主 `$262.gc()` 置位的强制收集与压力模式收集在此边界消费：
+                // 完整收集唯一安全点（无在途 dispatch 局部值），与正常触发路径
+                // 同一入口。压力模式开启后每个顶层边界做一次完整收集。
+                if self.gc_state.pending_forced_collect || self.gc_state.gc_pressure_mode {
                     self.gc_state.pending_forced_collect = false;
                     self.collect_session_gc();
                 }
@@ -141,13 +142,15 @@ impl Vm {
                 if alloc > self.gc_state.run_alloc_peak {
                     self.gc_state.run_alloc_peak = alloc;
                 }
-                if bytes >= self.gc_state.string_gc_watermark {
+                // 压力模式开启时跳过两档水位收集：完整收集已涵盖其全部工作，
+                // 同边界双触发只会多一轮空转 mark。
+                if bytes >= self.gc_state.string_gc_watermark && !self.gc_state.gc_pressure_mode {
                     self.maybe_collect_session_strings();
                 }
                 // 执行期原地 sweep 收集：O(1) 包络超触发水位 → 收集（无门控：
                 // 迭代器键引用经根收集标活，原地释放不搬移存活对象；
                 // 边界契约见 maybe_collect_in_run）。
-                if alloc >= self.gc_state.gc_watermark {
+                if alloc >= self.gc_state.gc_watermark && !self.gc_state.gc_pressure_mode {
                     self.maybe_collect_in_run();
                 }
             }
diff --git a/crates/oxide_vm/src/vm_state.rs b/crates/oxide_vm/src/vm_state.rs
index 463db3f3..ead649e7 100644
--- a/crates/oxide_vm/src/vm_state.rs
+++ b/crates/oxide_vm/src/vm_state.rs
@@ -57,6 +57,10 @@ pub(crate) struct GcState {
     /// 宿主强制收集旗标（`$262.gc()`）：native 重入中置位，由下一个顶层
     /// 指令边界（完整收集的唯一安全点：无在途 builtin 局部裸指针）消费。
     pub(crate) pending_forced_collect: bool,
+    /// GC 压力模式开关（构造时读环境变量 `OXIDE_GC_PRESSURE`，存在即开）：
+    /// 开启后每个顶层指令边界做一次完整收集，与强制收集共用同一安全点入口，
+    /// 同时跳过两个水位触发的档（完整收集已涵盖其全部工作）。
+    pub(crate) gc_pressure_mode: bool,
 }
 
 impl GcState {
diff --git a/crates/oxide_vm/src/vm_support.rs b/crates/oxide_vm/src/vm_support.rs
index 4193d729..87fcc1d4 100644
--- a/crates/oxide_vm/src/vm_support.rs
+++ b/crates/oxide_vm/src/vm_support.rs
@@ -15,6 +15,15 @@ use oxide_types::mem::P;
 use oxide_types::object::{JsObject, JsString, PropAttributes};
 use oxide_types::value::JsValue;
 
+/// 读 GC 压力模式开关：环境变量 `OXIDE_GC_PRESSURE` 存在即开启（取值不解析）。
+///
+/// 每次 VM 构造读一次，不做进程级缓存——缓存会在测试二进制内先构造的 VM 处
+/// 锁死取值，后跑的测试再设环境变量不生效。VM 构造不是热路径（每测试/每池/
+/// 每进程一次），读环境变量的开销可忽略。
+fn gc_pressure_mode_from_env() -> bool {
+    std::env::var_os("OXIDE_GC_PRESSURE").is_some()
+}
+
 impl Vm {
     /// Cons（rope）节点保留的单元阈值：拼接总长（UTF-16 单元数）≤ 该值时
     /// 急切扁平。小链的"链接 + 首次消费扁平化"双重分配高于直接拷贝，直接
@@ -138,6 +147,7 @@ impl Vm {
                 gc_threshold_cached: gc_threshold,
                 gc_watermark: gc_threshold,
                 pending_forced_collect: false,
+                gc_pressure_mode: gc_pressure_mode_from_env(),
             },
             symbols: SymbolState {
                 symbol_counter: 0,
@@ -282,6 +292,7 @@ impl Vm {
                 gc_threshold_cached: gc_threshold,
                 gc_watermark: gc_threshold,
                 pending_forced_collect: false,
+                gc_pressure_mode: gc_pressure_mode_from_env(),
             },
             symbols: SymbolState {
                 symbol_counter: 0,
diff --git a/crates/oxide_vm/tests/gc_stress_tests.rs b/crates/oxide_vm/tests/gc_stress_tests.rs
new file mode 100644
index 00000000..a9a31010
--- /dev/null
+++ b/crates/oxide_vm/tests/gc_stress_tests.rs
@@ -0,0 +1,57 @@
+//! GC 压力模式开关验证：环境变量 `OXIDE_GC_PRESSURE` 存在即开启，开启后每个
+//! 顶层指令边界做一次完整收集（与 `$262.gc()` 强制收集共用同一安全点入口），
+//! 缺省时行为与现状完全一致。
+//!
+//! 单测试函数内顺序跑开/关两臂：同一文件内多测试并行会竞争 `set_var`，
+//! 单函数顺序执行免除该竞争（环境变量为进程级，跨测试二进制天然隔离）。
+
+use std::sync::Arc;
+
+use oxide_compiler::compiler::Compiler;
+use oxide_parser::Allocator;
+use oxide_types::value::JsValue;
+use oxide_vm::vm::Vm;
+
+/// 单测辅助：在调用方提供的 VM 上编译并执行源串，返回原始结果值。
+fn eval_on(vm: &mut Vm, source: &str) -> Result<JsValue, String> {
+    let allocator = Allocator::default();
+    let program = oxide_parser::parse(&allocator, source).map_err(|e| format!("parse error: {}", e[0].message))?;
+    let module = Compiler::new().compile(&program).map_err(|e| format!("compile error: {e}"))?;
+    vm.run(&Arc::new(module))
+}
+
+/// 带分配的短脚本：全局可达对象 + 100 次循环字符串分配（产生大量顶层指令边界）。
+/// 末条表达式同时是存活钉：对象身份（`$262.global.o === globalThis.o`）与
+/// 属性读回（`x + s.length === 46`）在反复收集后必须保持完整。
+const SCRIPT: &str = "(function () { \
+  globalThis.o = { x: 41, s: 'keep' }; \
+  globalThis.o.x = 42; \
+  for (var i = 0; i < 100; i++) { var t = 'str' + i; } \
+  return globalThis.o.x + globalThis.o.s.length === 46 \
+     && $262.global.o === globalThis.o; })()";
+
+/// 开臂：压力模式开启后每个顶层边界做一次完整收集，收集计数与顶层指令边界数
+/// 同量级（100 次循环迭代至少 100 个边界），全局可达对象身份与属性读回完整。
+/// 关臂：同一脚本在缺省环境下退化为现状——小脚本分配不超水位，零收集。
+#[test]
+fn gc_pressure_mode_env_toggle() {
+    // 开臂：设环境变量后构造 VM（每次构造读环境变量，不缓存）。
+    std::env::set_var("OXIDE_GC_PRESSURE", "1");
+    let mut vm = Vm::new();
+    let result = eval_on(&mut vm, SCRIPT).expect("脚本不应运行失败");
+    assert!(result.as_bool(), "存活钉读回应完整");
+    let total = vm.session_gc_stats().total_collections;
+    assert!(
+        total > 100,
+        "压力模式应每个顶层边界做一次完整收集，实际 {total}"
+    );
+    // 关臂：移除环境变量后同一脚本走退化路径。
+    std::env::remove_var("OXIDE_GC_PRESSURE");
+    let mut vm = Vm::new();
+    let result = eval_on(&mut vm, SCRIPT).expect("脚本不应运行失败");
+    assert!(result.as_bool(), "存活钉读回应完整");
+    assert_eq!(
+        vm.session_gc_stats().total_collections, 0,
+        "关臂小脚本分配不超水位，收集应为零"
+    );
+}