scale the socket receive buffer on the fly #39062

nodejs · Jun 26, 2021 · 4bbfec7 · 4bbfec7
1 parent fdb097c
commit 4bbfec7
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Showing 2 changed files with 15 additions and 2 deletions.
diff --git a/src/stream_wrap.cc b/src/stream_wrap.cc
@@ -117,7 +117,8 @@ LibuvStreamWrap::LibuvStreamWrap(Environment* env,
                  reinterpret_cast<uv_handle_t*>(stream),
                  provider),
       StreamBase(env),
-      stream_(stream) {
+      stream_(stream),
+      recvQSize(STREAM_WRAP_RECVQ_INITIAL) {
   StreamBase::AttachToObject(object);
 }
 
@@ -209,7 +210,7 @@ void LibuvStreamWrap::OnUvAlloc(size_t suggested_size, uv_buf_t* buf) {
   HandleScope scope(env()->isolate());
   Context::Scope context_scope(env()->context());
 
-  *buf = EmitAlloc(suggested_size);
+  *buf = EmitAlloc(recvQSize);
 }
 
 template <class WrapType>
@@ -252,6 +253,13 @@ void LibuvStreamWrap::OnUvRead(ssize_t nread, const uv_buf_t* buf) {
   CHECK_EQ(persistent().IsEmpty(), false);
 
   if (nread > 0) {
+    // Adjust the dynamic receive buffer
+    if (nread == recvQSize && recvQSize < STREAM_WRAP_RECVQ_MAX) {
+      recvQSize <<= 1;
+    } else if (nread < recvQSize / 4 && recvQSize > STREAM_WRAP_RECVQ_MIN) {
+      recvQSize >>= 1;
+    }
+
     MaybeLocal<Object> pending_obj;
 
     if (type == UV_TCP) {

diff --git a/src/stream_wrap.h b/src/stream_wrap.h
@@ -28,6 +28,10 @@
 #include "handle_wrap.h"
 #include "v8.h"
 
+#define STREAM_WRAP_RECVQ_INITIAL   16*1024
+#define STREAM_WRAP_RECVQ_MIN       16*1024
+#define STREAM_WRAP_RECVQ_MAX       256*1024
+
 namespace node {
 
 class Environment;
@@ -111,6 +115,7 @@ class LibuvStreamWrap : public HandleWrap, public StreamBase {
   static void AfterUvShutdown(uv_shutdown_t* req, int status);
 
   uv_stream_t* const stream_;
+  ssize_t recvQSize;
 
 #ifdef _WIN32
   // We don't always have an FD that we could look up on the stream_