perf: use available system memory for v8 isolate memory limit (#26868)

Instead of using the default 1.4Gb limit (which was meant for browser
tabs) configure V8 to
set the heap limit to the amount of memory available in the system.

Closes https://github.com/denoland/deno/issues/23424
Closes https://github.com/denoland/deno/issues/26435
Closes https://github.com/denoland/deno/issues/21226

cli/lsp/tsc.rs

@@ -34,6 +34,7 @@ use crate::util::path::relative_specifier;
 use crate::util::path::to_percent_decoded_str;
 use crate::util::result::InfallibleResultExt;
 use crate::util::v8::convert;
+use crate::worker::create_isolate_create_params;
 use deno_core::convert::Smi;
 use deno_core::convert::ToV8;
 use deno_core::error::StdAnyError;
@@ -4760,6 +4761,7 @@ fn run_tsc_thread(
       specifier_map,
       request_rx,
     )],
+    create_params: create_isolate_create_params(),
     startup_snapshot: Some(tsc::compiler_snapshot()),
     inspector: has_inspector_server,
     ..Default::default()

cli/tsc/mod.rs

@@ -9,6 +9,7 @@ use crate::npm::CliNpmResolver;
 use crate::resolver::CjsTracker;
 use crate::util::checksum;
 use crate::util::path::mapped_specifier_for_tsc;
+use crate::worker::create_isolate_create_params;
 
 use deno_ast::MediaType;
 use deno_core::anyhow::anyhow;
@@ -1104,6 +1105,7 @@ pub fn exec(request: Request) -> Result<Response, AnyError> {
       root_map,
       remapped_specifiers,
     )],
+    create_params: create_isolate_create_params(),
     ..Default::default()
   });
 

cli/worker.rs

@@ -555,6 +555,7 @@ impl CliMainWorkerFactory {
       permissions,
       v8_code_cache: shared.code_cache.clone(),
     };
+
     let options = WorkerOptions {
       bootstrap: BootstrapOptions {
         deno_version: crate::version::DENO_VERSION_INFO.deno.to_string(),
@@ -585,7 +586,7 @@ impl CliMainWorkerFactory {
       },
       extensions: custom_extensions,
       startup_snapshot: crate::js::deno_isolate_init(),
-      create_params: None,
+      create_params: create_isolate_create_params(),
       unsafely_ignore_certificate_errors: shared
         .options
         .unsafely_ignore_certificate_errors
@@ -786,6 +787,7 @@ fn create_web_worker_callback(
       },
       extensions: vec![],
       startup_snapshot: crate::js::deno_isolate_init(),
+      create_params: create_isolate_create_params(),
       unsafely_ignore_certificate_errors: shared
         .options
         .unsafely_ignore_certificate_errors
@@ -806,6 +808,17 @@ fn create_web_worker_callback(
   })
 }
 
+/// By default V8 uses 1.4Gb heap limit which is meant for browser tabs.
+/// 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::sys_info::mem_info();
+  maybe_mem_info.map(|mem_info| {
+    v8::CreateParams::default()
+      .heap_limits_from_system_memory(mem_info.total, 0)
+  })
+}
+
 #[allow(clippy::print_stdout)]
 #[allow(clippy::print_stderr)]
 #[cfg(test)]

runtime/lib.rs

@@ -35,6 +35,7 @@ pub mod js;
 pub mod ops;
 pub mod permissions;
 pub mod snapshot;
+pub mod sys_info;
 pub mod tokio_util;
 pub mod web_worker;
 pub mod worker;

runtime/ops/os/mod.rs

@@ -1,5 +1,6 @@
 // Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
 
+use crate::sys_info;
 use crate::worker::ExitCode;
 use deno_core::op2;
 use deno_core::v8;
@@ -11,8 +12,6 @@ use serde::Serialize;
 use std::collections::HashMap;
 use std::env;
 
-mod sys_info;
-
 deno_core::extension!(
   deno_os,
   ops = [

runtime/web_worker.rs

@@ -361,6 +361,8 @@ pub struct WebWorkerOptions {
   pub extensions: Vec<Extension>,
   pub startup_snapshot: Option<&'static [u8]>,
   pub unsafely_ignore_certificate_errors: Option<Vec<String>>,
+  /// Optional isolate creation parameters, such as heap limits.
+  pub create_params: Option<v8::CreateParams>,
   pub seed: Option<u64>,
   pub create_web_worker_cb: Arc<ops::worker_host::CreateWebWorkerCb>,
   pub format_js_error_fn: Option<Arc<FormatJsErrorFn>>,
@@ -563,6 +565,7 @@ impl WebWorker {
     let mut js_runtime = JsRuntime::new(RuntimeOptions {
       module_loader: Some(services.module_loader),
       startup_snapshot: options.startup_snapshot,
+      create_params: options.create_params,
       get_error_class_fn: options.get_error_class_fn,
       shared_array_buffer_store: services.shared_array_buffer_store,
       compiled_wasm_module_store: services.compiled_wasm_module_store,