fix(cli): configure v8 isolate with cgroups-constrained memory limit

This change configures V8 isolates to respect memory limits imposed by
cgroups on Linux. It adds support for detecting both cgroups v1 and v2
memory limits, enabling Deno to properly adapt to containerized
environments with memory constraints. When cgroups information is
unavailable or not applicable, it falls back to using the system's
total memory as before.

Author: magurotuna

cli/lib/worker.rs

@@ -130,11 +130,65 @@ pub fn get_cache_storage_dir() -> PathBuf {
 /// Instead probe for the total memory on the system and use it instead
 /// as a default.
 pub fn create_isolate_create_params() -> Option<v8::CreateParams> {
-  let maybe_mem_info = deno_runtime::deno_os::sys_info::mem_info();
-  maybe_mem_info.map(|mem_info| {
-    v8::CreateParams::default()
-      .heap_limits_from_system_memory(mem_info.total, 0)
-  })
+  #[cfg(any(target_os = "android", target_os = "linux"))]
+  {
+    get_memory_limit_linux().map(|memory_limit| {
+      v8::CreateParams::default()
+        .heap_limits_from_system_memory(memory_limit, 0)
+    })
+  }
+  #[cfg(not(any(target_os = "android", target_os = "linux")))]
+  {
+    let maybe_mem_info = deno_runtime::deno_os::sys_info::mem_info();
+    maybe_mem_info.map(|mem_info| {
+      v8::CreateParams::default()
+        .heap_limits_from_system_memory(mem_info.total, 0)
+    })
+  }
+}
+
+/// Get memory limit with cgroup (either v1 or v2) taken into account.
+#[cfg(any(target_os = "android", target_os = "linux"))]
+fn get_memory_limit_linux() -> Option<u64> {
+  let system_total_memory =
+    deno_runtime::deno_os::sys_info::mem_info().map(|mem_info| mem_info.total);
+
+  let Ok(self_cgroup) = std::fs::read_to_string("/proc/self/cgroup") else {
+    return system_total_memory;
+  };
+
+  let limit = match self_cgroup.strip_prefix("0::/") {
+    Some(cgroup_v2_relpath) => {
+      // cgroup v2
+      let limit_path = std::path::Path::new("/sys/fs/cgroup")
+        .join(cgroup_v2_relpath)
+        .join("memory.max");
+      std::fs::read_to_string(limit_path)
+        .ok()
+        .and_then(|s| s.trim().parse::<u64>().ok())
+    }
+    None => {
+      // cgroup v1
+      let Some(cgroup_v1_relpath) = self_cgroup.lines().find_map(|l| {
+        let split = l.split(":").collect::<Vec<_>>();
+        if split.get(1) == Some(&"memory") {
+          split.get(2)
+        } else {
+          None
+        }
+      }) else {
+        return system_total_memory;
+      };
+      let limit_path = std::path::Path::new("/sys/fs/cgroup/memory")
+        .join(cgroup_v1_relpath)
+        .join("memory.limit_in_bytes");
+      std::fs::read_to_string(limit_path)
+        .ok()
+        .and_then(|s| s.trim().parse::<u64>().ok())
+    }
+  };
+
+  limit.or(system_total_memory)
 }
 
 #[derive(Debug, thiserror::Error, deno_error::JsError)]