Move memoryUsage() into C on Linux

lib/sys.js

@@ -67,64 +67,3 @@ exports.exec = function (command) {
 
   return promise;
 };
-
-exports.memoryUsage = function () {
-  if (process.platform == "linux2") {
-    var data = require("file").read("/proc/self/stat").wait();
-    // from linux-2.6.29/Documentation/filesystems/proc.tx
-    // 0   pid           process id
-    // 1   tcomm         filename of the executable
-    // 2   state         state (R is running, S is sleeping, D is sleeping in an
-    //                   uninterruptible wait, Z is zombie, T is traced or stopped)
-    // 3   ppid          process id of the parent process
-    // 4   pgrp          pgrp of the process
-    // 5   sid           session id
-    // 6   tty_nr        tty the process uses
-    // 7   tty_pgrp      pgrp of the tty
-    // 8   flags         task flags
-    // 9   min_flt       number of minor faults
-    // 10  cmin_flt      number of minor faults with child's
-    // 11  maj_flt       number of major faults
-    // 12  cmaj_flt      number of major faults with child's
-    // 13  utime         user mode jiffies
-    // 14  stime         kernel mode jiffies
-    // 15  cutime        user mode jiffies with child's
-    // 16  cstime        kernel mode jiffies with child's
-    // 17  priority      priority level
-    // 18  nice          nice level
-    // 19  num_threads   number of threads
-    // 20  it_real_value	(obsolete, always 0)
-    // 21  start_time    time the process started after system boot
-    // 22  vsize         virtual memory size
-    // 23  rss           resident set memory size
-    // 24  rsslim        current limit in bytes on the rss
-    // 25  start_code    address above which program text can run
-    // 26  end_code      address below which program text can run
-    // 27  start_stack   address of the start of the stack
-    // 28  esp           current value of ESP
-    // 29  eip           current value of EIP
-    // 30  pending       bitmap of pending signals (obsolete)
-    // 31  blocked       bitmap of blocked signals (obsolete)
-    // 32  sigign        bitmap of ignored signals (obsolete)
-    // 33  sigcatch      bitmap of catched signals (obsolete)
-    // 34  wchan         address where process went to sleep
-    // 35  0             (place holder)
-    // 36  0             (place holder)
-    // 37  exit_signal   signal to send to parent thread on exit
-    // 38  task_cpu      which CPU the task is scheduled on
-    // 39  rt_priority   realtime priority
-    // 40  policy        scheduling policy (man sched_setscheduler)
-    // 41  blkio_ticks   time spent waiting for block IO
-    var fields = data.split(" ");
-
-    // 22  vsize         virtual memory size
-    // 23  rss           resident set memory size
-
-    return { vsize: parseInt(fields[22]), rss: 4096*parseInt(fields[23]) };
-
-  } else if (process.platform == "darwin") {
-    return process.macGetMemory();
-  } else {
-    throw new Error("Unsupported on your platform! Complain to Ryan!");
-  }
-};

src/node.cc

@@ -254,17 +254,15 @@ v8::Handle<v8::Value> Exit(const v8::Arguments& args) {
 }
 
 #ifdef __APPLE__
+#define HAVE_GETMEM 1
 /* Researched by Tim Becker and Michael Knight
- * http://blog.kuriositaet.de/?p=257
  * http://blog.kuriositaet.de/?p=257
  */
 
 #include <mach/task.h>
 #include <mach/mach_init.h>
 
-v8::Handle<v8::Value> MacGetMemory(const v8::Arguments& args) {
+int getmem(size_t *rss, size_t *vsize) {
-  HandleScope scope;
-
   task_t task = MACH_PORT_NULL;
   struct task_basic_info t_info;
   mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;
@@ -274,21 +272,123 @@ v8::Handle<v8::Value> MacGetMemory(const v8::Arguments& args) {
                     (task_info_t)&t_info,
                     &t_info_count);
 
-  if (KERN_SUCCESS != r) {
+  if (r != KERN_SUCCESS) return -1;
+
+  *rss = t_info.resident_size;
+  *vsize  = t_info.virtual_size;
+
+  return 0;
+}
+#endif  // __APPLE__
+
+#ifdef __linux__
+# define HAVE_GETMEM 1
+# include <sys/param.h> /* for MAXPATHLEN */
+# include <sys/user.h> /* for PAGE_SIZE */
+
+int getmem(size_t *rss, size_t *vsize) {
+  FILE *f = fopen("/proc/self/stat", "r");
+  if (!f) return -1;
+
+  int itmp;
+  char ctmp;
+  char buffer[MAXPATHLEN];
+
+  /* PID */
+  if (fscanf(f, "%d ", &itmp) == 0) goto error;
+  /* Exec file */
+  if (fscanf (f, "%s ", &buffer[0]) == 0) goto error;
+  /* State */
+  if (fscanf (f, "%c ", &ctmp) == 0) goto error;
+  /* Parent process */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* Process group */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* Session id */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* TTY */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* TTY owner process group */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* Flags */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Minor faults (no memory page) */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Minor faults, children */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Major faults (memory page faults) */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Major faults, children */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* utime */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* stime */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* utime, children */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* stime, children */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* jiffies remaining in current time slice */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* 'nice' value */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+  /* jiffies until next timeout */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* jiffies until next SIGALRM */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* start time (jiffies since system boot) */
+  if (fscanf (f, "%d ", &itmp) == 0) goto error;
+
+  /* Virtual memory size */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  *vsize = (size_t) itmp;
+
+  /* Resident set size */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  *rss = (size_t) itmp * PAGE_SIZE;
+
+  /* rlim */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Start of text */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* End of text */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+  /* Start of stack */
+  if (fscanf (f, "%u ", &itmp) == 0) goto error;
+
+  fclose (f);
+
+  return 0;
+
+error:
+  fclose (f);
+  return -1;
+}
+#endif  // __linux__
+
+v8::Handle<v8::Value> MemoryUsage(const v8::Arguments& args) {
+  HandleScope scope;
+
+#ifndef HAVE_GETMEM
+  return ThrowException(Exception::Error(String::New("Not support on your platform. (Talk to Ryan.)")));
+#else
+  size_t rss, vsize;
+
+  int r = getmem(&rss, &vsize);
+
+  if (r != 0) {
     return ThrowException(Exception::Error(String::New(strerror(errno))));
   }
 
-  size_t rss = t_info.resident_size;
-  size_t vs  = t_info.virtual_size;
-
   Local<Object> info = Object::New();
 
   info->Set(String::NewSymbol("rss"), Integer::NewFromUnsigned(rss));
-  info->Set(String::NewSymbol("vsize"), Integer::NewFromUnsigned(vs));
+  info->Set(String::NewSymbol("vsize"), Integer::NewFromUnsigned(vsize));
 
   return scope.Close(info);
+#endif
 }
-#endif  // __APPLE__
+
 
 v8::Handle<v8::Value> Kill(const v8::Arguments& args) {
   HandleScope scope;
@@ -510,9 +610,7 @@ static Local<Object> Load(int argc, char *argv[]) {
   NODE_SET_METHOD(process, "cwd", Cwd);
   NODE_SET_METHOD(process, "dlopen", DLOpen);
   NODE_SET_METHOD(process, "kill", Kill);
-#ifdef __APPLE__
+  NODE_SET_METHOD(process, "memoryUsage", MemoryUsage);
-  NODE_SET_METHOD(process, "macGetMemory", MacGetMemory);
-#endif
 
   // Assign the EventEmitter. It was created in main().
   process->Set(String::NewSymbol("EventEmitter"),

test/mjsunit/test-memory-usage.js

@@ -1,6 +1,6 @@
 process.mixin(require("./common"));
 
-var r = memoryUsage();
+var r = process.memoryUsage();
 puts(inspect(r));
 assertTrue(r["rss"] > 0);
 assertTrue(r["vsize"] > 0);