fs: improve performance for sync stat() functions

PR-URL: #11522
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: mscdex

benchmark/fs/bench-statSync.js

@@ -5,17 +5,35 @@ const fs = require('fs');
 
 constbench=common.createBenchmark(main,{
 n: [1e4],
-kind: ['lstatSync','statSync']
+kind: ['fstatSync','lstatSync','statSync']
 });
 
 
 functionmain(conf){
 constn=conf.n>>>0;
-constfn=fs[conf.kind];
-
-bench.start();
-for(vari=0;i<n;i++){
-fn(__filename);
+varfn;
+vari;
+switch(conf.kind){
+case'statSync':
+case'lstatSync':
+fn=fs[conf.kind];
+bench.start();
+for(i=0;i<n;i++){
+fn(__filename);
+}
+bench.end(n);
+break;
+case'fstatSync':
+fn=fs.fstatSync;
+constfd=fs.openSync(__filename,'r');
+bench.start();
+for(i=0;i<n;i++){
+fn(fd);
+}
+bench.end(n);
+fs.closeSync(fd);
+break;
+default:
+thrownewError('Invalid kind argument');
 }
-bench.end(n);
 }

lib/fs.js

@@ -147,7 +147,7 @@ function isFd(path) {
 }
 
 // Static method to set the stats properties on a Stats object.
-fs.Stats=function(
+functionStats(
 dev,
 mode,
 nlink,
@@ -176,7 +176,8 @@ fs.Stats = function(
 this.mtime=newDate(mtim_msec);
 this.ctime=newDate(ctim_msec);
 this.birthtime=newDate(birthtim_msec);
-};
+}
+fs.Stats=Stats;
 
 // Create a C++ binding to the function which creates a Stats object.
 binding.FSInitialize(fs.Stats);
@@ -261,7 +262,7 @@ fs.exists = function(path, callback) {
 fs.existsSync=function(path){
 try{
 nullCheck(path);
-binding.stat(pathModule._makeLong(path));
+binding.stat(pathModule._makeLong(path),statValues);
 returntrue;
 }catch(e){
 returnfalse;
@@ -973,18 +974,31 @@ fs.stat = function(path, callback) {
 binding.stat(pathModule._makeLong(path),req);
 };
 
+conststatValues=newFloat64Array(14);
+functionstatsFromValues(){
+returnnewStats(statValues[0],statValues[1],statValues[2],statValues[3],
+statValues[4],statValues[5],
+statValues[6]<0 ? undefined : statValues[6],statValues[7],
+statValues[8],statValues[9]<0 ? undefined : statValues[9],
+statValues[10],statValues[11],statValues[12],
+statValues[13]);
+}
+
 fs.fstatSync=function(fd){
-returnbinding.fstat(fd);
+binding.fstat(fd,statValues);
+returnstatsFromValues();
 };
 
 fs.lstatSync=function(path){
 nullCheck(path);
-returnbinding.lstat(pathModule._makeLong(path));
+binding.lstat(pathModule._makeLong(path),statValues);
+returnstatsFromValues();
 };
 
 fs.statSync=function(path){
 nullCheck(path);
-returnbinding.stat(pathModule._makeLong(path));
+binding.stat(pathModule._makeLong(path),statValues);
+returnstatsFromValues();
 };
 
 fs.readlink=function(path,options,callback){

src/node_file.cc

@@ -27,8 +27,10 @@
 namespacenode {
 
 using v8::Array;
+using v8::ArrayBuffer;
 using v8::Context;
 using v8::EscapableHandleScope;
+using v8::Float64Array;
 using v8::Function;
 using v8::FunctionCallbackInfo;
 using v8::FunctionTemplate;
@@ -528,6 +530,37 @@ Local<Value> BuildStatsObject(Environment* env, const uv_stat_t* s) {
 return handle_scope.Escape(stats);
 }
 
+voidFillStatsArray(double* fields, constuv_stat_t* s) {
+ fields[0] = s->st_dev;
+ fields[1] = s->st_mode;
+ fields[2] = s->st_nlink;
+ fields[3] = s->st_uid;
+ fields[4] = s->st_gid;
+ fields[5] = s->st_rdev;
+#if defined(__POSIX__)
+ fields[6] = s->st_blksize;
+#else
+ fields[6] = -1;
+#endif
+ fields[7] = s->st_ino;
+ fields[8] = s->st_size;
+#if defined(__POSIX__)
+ fields[9] = s->st_blocks;
+#else
+ fields[9] = -1;
+#endif
+// Dates.
+#defineX(idx, name) \
+ fields[idx] = (static_cast<double>(s->st_##name.tv_sec) * 1000) + \
+ (static_cast<double>(s->st_##name.tv_nsec / 1000000)); \
+
+X(10, atim)
+X(11, mtim)
+X(12, ctim)
+X(13, birthtim)
+#undef X
+}
+
 // Used to speed up module loading. Returns the contents of the file as
 // a string or undefined when the file cannot be opened. The speedup
 // comes from not creating Error objects on failure.
@@ -618,12 +651,15 @@ static void Stat(const FunctionCallbackInfo<Value>& args) {
  BufferValue path(env->isolate(), args[0]);
 ASSERT_PATH(path)
 
-if (args[1]->IsObject()) {
-ASYNC_CALL(stat, args[1], UTF8, *path)
- } else {
+if (args[1]->IsFloat64Array()) {
+ Local<Float64Array> array = args[1].As<Float64Array>();
+CHECK_EQ(array->Length(), 14);
+ Local<ArrayBuffer> ab = array->Buffer();
+double* fields = static_cast<double*>(ab->GetContents().Data());
 SYNC_CALL(stat, *path, *path)
- args.GetReturnValue().Set(
-BuildStatsObject(env, static_cast<constuv_stat_t*>(SYNC_REQ.ptr)));
+FillStatsArray(fields, static_cast<constuv_stat_t*>(SYNC_REQ.ptr));
+ } elseif (args[1]->IsObject()) {
+ASYNC_CALL(stat, args[1], UTF8, *path)
  }
 }
 
@@ -636,12 +672,15 @@ static void LStat(const FunctionCallbackInfo<Value>& args) {
  BufferValue path(env->isolate(), args[0]);
 ASSERT_PATH(path)
 
-if (args[1]->IsObject()) {
-ASYNC_CALL(lstat, args[1], UTF8, *path)
- } else {
+if (args[1]->IsFloat64Array()) {
+ Local<Float64Array> array = args[1].As<Float64Array>();
+CHECK_EQ(array->Length(), 14);
+ Local<ArrayBuffer> ab = array->Buffer();
+double* fields = static_cast<double*>(ab->GetContents().Data());
 SYNC_CALL(lstat, *path, *path)
- args.GetReturnValue().Set(
-BuildStatsObject(env, static_cast<constuv_stat_t*>(SYNC_REQ.ptr)));
+FillStatsArray(fields, static_cast<constuv_stat_t*>(SYNC_REQ.ptr));
+ } elseif (args[1]->IsObject()) {
+ASYNC_CALL(lstat, args[1], UTF8, *path)
  }
 }
 
@@ -655,12 +694,15 @@ static void FStat(const FunctionCallbackInfo<Value>& args) {
 
 int fd = args[0]->Int32Value();
 
-if (args[1]->IsObject()) {
-ASYNC_CALL(fstat, args[1], UTF8, fd)
- } else {
+if (args[1]->IsFloat64Array()) {
+ Local<Float64Array> array = args[1].As<Float64Array>();
+CHECK_EQ(array->Length(), 14);
+ Local<ArrayBuffer> ab = array->Buffer();
+double* fields = static_cast<double*>(ab->GetContents().Data());
 SYNC_CALL(fstat, 0, fd)
- args.GetReturnValue().Set(
-BuildStatsObject(env, static_cast<constuv_stat_t*>(SYNC_REQ.ptr)));
+FillStatsArray(fields, static_cast<constuv_stat_t*>(SYNC_REQ.ptr));
+ } elseif (args[1]->IsObject()) {
+ASYNC_CALL(fstat, args[1], UTF8, fd)
  }
 }