child_process: serialize advanced IPC messages natively

The `advanced` IPC serialization codec was implemented in JavaScript
(ChildProcessSerializer / ChildProcessDeserializer in
lib/internal/child_process/serialization.js). It allocated a wrapper
serializer/deserializer per message and crossed the JS/C++ boundary
several times for every message (writeHeader, writeValue, releaseBuffer,
readHeader, readValue and friends).
Move the codec into a native `ipc_serdes` binding that drives the V8
ValueSerializer/ValueDeserializer with a C++ delegate. The wire format
is preserved byte-for-byte: a big-endian uint32 length prefix followed
by the V8 payload, with ArrayBufferViews tagged as host objects so that
Node Buffers round-trip as Buffers rather than plain Uint8Arrays. The
JSON codec is left unchanged.
A cctest (test/cctest/test_node_ipc_serdes.cc) exercises the binding
directly, covering round-trips of primitives, objects, typed arrays and
Buffers (including the Buffer-vs-Uint8Array distinction) and asserting
the big-endian length-prefix framing.
Round-trip throughput
(benchmark/child_process/child-process-ipc-roundtrip):
payload before after change
64 B ~300k/s ~800k/s +166%
1 KiB ~272k/s ~616k/s +126%
16 KiB ~91k/s ~120k/s +32%
64 KiB ~30k/s ~35k/s +16%
The gain is largest for small messages, where per-message JavaScript
overhead dominated, and tapers for large messages, where the actual
serialization (already native) dominates.
Signed-off-by: Yagiz Nizipli <yagiz@nizipli.com>
PR-URL: #63933
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Filip Skokan <panva.ip@gmail.com>

Author: anonrig

lib/internal/child_process/serialization.js

@@ -10,43 +10,14 @@ const {
 }=primordials;
 const{ Buffer }=require('buffer');
 const{ StringDecoder }=require('string_decoder');
-constv8=require('v8');
-const{ isArrayBufferView }=require('internal/util/types');
-constassert=require('internal/assert');
+const{ serialize, deserialize }=internalBinding('ipc_serdes');
 const{ streamBaseState, kLastWriteWasAsync }=internalBinding('stream_wrap');
 
 constkMessageBuffer=Symbol('kMessageBuffer');
 constkMessageBufferSize=Symbol('kMessageBufferSize');
 constkJSONBuffer=Symbol('kJSONBuffer');
 constkStringDecoder=Symbol('kStringDecoder');
 
-// Extend V8's serializer APIs to give more JSON-like behaviour in
-// some cases; in particular, for native objects this serializes them the same
-// way that JSON does rather than throwing an exception.
-constkArrayBufferViewTag=0;
-constkNotArrayBufferViewTag=1;
-classChildProcessSerializerextendsv8.DefaultSerializer{
-_writeHostObject(object){
-if(isArrayBufferView(object)){
-this.writeUint32(kArrayBufferViewTag);
-returnsuper._writeHostObject(object);
-}
-this.writeUint32(kNotArrayBufferViewTag);
-this.writeValue({ ...object});
-}
-}
-
-classChildProcessDeserializerextendsv8.DefaultDeserializer{
-_readHostObject(){
-consttag=this.readUint32();
-if(tag===kArrayBufferViewTag)
-returnsuper._readHostObject();
-
-assert(tag===kNotArrayBufferViewTag);
-returnthis.readValue();
-}
-}
-
 // Messages are parsed in either of the following formats:
 // - Newline-delimited JSON, or
 // - V8-serialized buffers, prefixed with their length as a big endian uint32
@@ -90,38 +61,25 @@ const advanced = {
 channel[kMessageBufferSize],
 );
 
-constdeserializer=newChildProcessDeserializer(
-TypedArrayPrototypeSubarray(concatenatedBuffer,4,fullMessageSize),
-);
+constserializedMessage=
+TypedArrayPrototypeSubarray(concatenatedBuffer,4,fullMessageSize);
 
 messageBufferHead=TypedArrayPrototypeSubarray(concatenatedBuffer,fullMessageSize);
 channel[kMessageBufferSize]=messageBufferHead.length;
 channel[kMessageBuffer]=
 channel[kMessageBufferSize]!==0 ? [messageBufferHead] : [];
 
-deserializer.readHeader();
-yielddeserializer.readValue();
+yielddeserialize(serializedMessage);
 }
 
 channel.buffering=channel[kMessageBufferSize]>0;
 },
 
 writeChannelMessage(channel,req,message,handle){
-constser=newChildProcessSerializer();
-// Add 4 bytes, to later populate with message length
-ser.writeRawBytes(Buffer.allocUnsafe(4));
-ser.writeHeader();
-ser.writeValue(message);
-
-constserializedMessage=ser.releaseBuffer();
-constserializedMessageLength=serializedMessage.length-4;
-
-serializedMessage.set([
-serializedMessageLength>>24&0xFF,
-serializedMessageLength>>16&0xFF,
-serializedMessageLength>>8&0xFF,
-serializedMessageLength&0xFF,
-],0);
+// Pass the stable Buffer constructor so the native codec can classify Node
+// Buffers via `value.constructor === Buffer` without reading the tamperable
+// Buffer.prototype.constructor.
+constserializedMessage=serialize(message,Buffer);
 
 constresult=channel.writeBuffer(req,serializedMessage,handle);
 

node.gyp

@@ -125,6 +125,7 @@
 'src/node_http_parser.cc',
 'src/node_http2.cc',
 'src/node_i18n.cc',
+'src/node_ipc_serdes.cc',
 'src/node_locks.cc',
 'src/node_main_instance.cc',
 'src/node_messaging.cc',

src/node_binding.cc

@@ -59,6 +59,7 @@
  V(http_parser) \
  V(inspector) \
  V(internal_only_v8) \
+ V(ipc_serdes) \
  V(js_stream) \
  V(js_udp_wrap) \
  V(locks) \

src/node_external_reference.h

@@ -82,6 +82,7 @@ class ExternalReferenceRegistry {
 V(heap_utils) \
 V(http_parser) \
 V(internal_only_v8) \
+V(ipc_serdes) \
 V(locks) \
 V(messaging) \
 V(mksnapshot) \