fs: improve error performance for writeSync

Author: pluris

benchmark/fs/bench-writeSync.js

@@ -0,0 +1,54 @@
+'use strict';
+
+const common = require('../common');
+const fs = require('fs');
+const assert = require('assert');
+const tmpdir = require('../../test/common/tmpdir');
+tmpdir.refresh();
+
+const path = tmpdir.resolve(`new-file-${process.pid}`);
+const parameters = [Buffer.from('Benchmark data'),
+                    0,
+                    Buffer.byteLength('Benchmark data')];
+const bench = common.createBenchmark(main, {
+  type: ['valid', 'invalid'],
+  n: [1e5],
+});
+
+function main({ n, type }) {
+  let fd;
+  let result;
+
+  switch (type) {
+    case 'valid':
+      fd = fs.openSync(path, 'w');
+
+      bench.start();
+      for (let i = 0; i < n; i++) {
+        result = fs.writeSync(fd, ...parameters);
+      }
+
+      bench.end(n);
+      assert(result);
+      fs.closeSync(fd);
+      break;
+    case 'invalid': {
+      fd = 1 << 30;
+      let hasError = false;
+      bench.start();
+      for (let i = 0; i < n; i++) {
+        try {
+          result = fs.writeSync(fd, ...parameters);
+        } catch {
+          hasError = true;
+        }
+      }
+
+      bench.end(n);
+      assert(hasError);
+      break;
+    }
+    default:
+      throw new Error('Invalid type');
+  }
+}

lib/fs.js

@@ -896,7 +896,6 @@ ObjectDefineProperty(write, kCustomPromisifyArgsSymbol,
  */
 function writeSync(fd, buffer, offsetOrOptions, length, position) {
   fd = getValidatedFd(fd);
-  const ctx = {};
   let result;
 
   let offset = offsetOrOptions;
@@ -918,18 +917,15 @@ function writeSync(fd, buffer, offsetOrOptions, length, position) {
     if (typeof length !== 'number')
       length = buffer.byteLength - offset;
     validateOffsetLengthWrite(offset, length, buffer.byteLength);
-    result = binding.writeBuffer(fd, buffer, offset, length, position,
-                                 undefined, ctx);
+    result = binding.writeBuffer(fd, buffer, offset, length, position);
   } else {
     validateStringAfterArrayBufferView(buffer, 'buffer');
     validateEncoding(buffer, length);
 
     if (offset === undefined)
       offset = null;
-    result = binding.writeString(fd, buffer, offset, length,
-                                 undefined, ctx);
+    result = binding.writeString(fd, buffer, offset, length);
   }
-  handleErrorFromBinding(ctx);
   return result;
 }
 

src/node_file.cc

@@ -2031,7 +2031,7 @@ static void WriteBuffer(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
 
   const int argc = args.Length();
-  CHECK_GE(argc, 4);
+  CHECK_GE(argc, 5);
 
   CHECK(args[0]->IsInt32());
   const int fd = args[0].As<Int32>()->Value();
@@ -2058,18 +2058,22 @@ static void WriteBuffer(const FunctionCallbackInfo<Value>& args) {
   char* buf = buffer_data + off;
   uv_buf_t uvbuf = uv_buf_init(buf, len);
 
-  FSReqBase* req_wrap_async = GetReqWrap(args, 5);
-  if (req_wrap_async != nullptr) {  // write(fd, buffer, off, len, pos, req)
+  if (argc > 5) {  // write(fd, buffer, off, len, pos, req)
+    FSReqBase* req_wrap_async = GetReqWrap(args, 5);
     FS_ASYNC_TRACE_BEGIN0(UV_FS_WRITE, req_wrap_async)
     AsyncCall(env, req_wrap_async, args, "write", UTF8, AfterInteger,
               uv_fs_write, fd, &uvbuf, 1, pos);
-  } else {  // write(fd, buffer, off, len, pos, undefined, ctx)
-    CHECK_EQ(argc, 7);
-    FSReqWrapSync req_wrap_sync;
+  } else {  // write(fd, buffer, off, len, pos)
+    FSReqWrapSync req_wrap_sync("write");
     FS_SYNC_TRACE_BEGIN(write);
-    int bytesWritten = SyncCall(env, args[6], &req_wrap_sync, "write",
-                                uv_fs_write, fd, &uvbuf, 1, pos);
+    int bytesWritten = SyncCallAndThrowOnError(
+        env, &req_wrap_sync, uv_fs_write, fd, &uvbuf, 1, pos);
     FS_SYNC_TRACE_END(write, "bytesWritten", bytesWritten);
+
+    if (is_uv_error(bytesWritten)) {
+      return;
+    }
+
     args.GetReturnValue().Set(bytesWritten);
   }
 }
@@ -2206,9 +2210,8 @@ static void WriteString(const FunctionCallbackInfo<Value>& args) {
     } else {
       req_wrap_async->SetReturnValue(args);
     }
-  } else {  // write(fd, string, pos, enc, undefined, ctx)
-    CHECK_EQ(argc, 6);
-    FSReqWrapSync req_wrap_sync;
+  } else {  // write(fd, string, pos, enc)
+    FSReqWrapSync req_wrap_sync("write");
     FSReqBase::FSReqBuffer stack_buffer;
     if (buf == nullptr) {
       if (!StringBytes::StorageSize(isolate, value, enc).To(&len))
@@ -2223,9 +2226,14 @@ static void WriteString(const FunctionCallbackInfo<Value>& args) {
     }
     uv_buf_t uvbuf = uv_buf_init(buf, len);
     FS_SYNC_TRACE_BEGIN(write);
-    int bytesWritten = SyncCall(env, args[5], &req_wrap_sync, "write",
-                                uv_fs_write, fd, &uvbuf, 1, pos);
+    int bytesWritten = SyncCallAndThrowOnError(
+        env, &req_wrap_sync, uv_fs_write, fd, &uvbuf, 1, pos);
     FS_SYNC_TRACE_END(write, "bytesWritten", bytesWritten);
+
+    if (is_uv_error(bytesWritten)) {
+      return;
+    }
+
     args.GetReturnValue().Set(bytesWritten);
   }
 }