bnoordhuis

// Copyright (c) 2014, Ben Noordhuis <info@bnoordhuis.nl>
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

bnoordhuis

// Compile at -O0 and -O1 or higher and compare the output of
// `strace -e pwritev a.out`. At -O0:
//
//    pwritev(1, [{"Hello ", 6}, {"world!", 6}, {"\n", 1}], 3, 0) = -1 ESPIPE
//    (Illegal seek)
//
// At -O1 or higher:
//
//    pwritev(1, [{"", 0}, {"H\211l$\330L\211d$\340H\215-\367\10 \0L\215%\350\10
//    \0H\211\\$\320L\211l"..., 4195360}, {"", 0}], 3, 0) = -1 ESPIPE (Illegal

bnoordhuis

[root@server ~]# strace -fp 5497
Process 5497 attached with 2 threads - interrupt to quit
[pid  5498] futex(0x7fa1b80008c8, FUTEX_WAIT_PRIVATE, 0, NULL <unfinished ...>
[pid  5497] epoll_wait(5, {{EPOLLIN, {u32=10, u64=10}}}, 1024, 4294967295) = 1
[pid  5497] accept4(10, 0, NULL, SOCK_CLOEXEC|SOCK_NONBLOCK) = 11
[pid  5497] futex(0x7fa1b80008c8, FUTEX_WAKE_PRIVATE, 1) = 1
[pid  5498] <... futex resumed> )       = 0
[pid  5498] nanosleep({0, 900000}, NULL) = 0
[pid  5498] futex(0x7fa1b80008c8, FUTEX_WAIT_PRIVATE, 0, NULL <unfinished ...>
[pid  5497] futex(0x7fa1b80008c8, FUTEX_WAKE_PRIVATE, 1 <unfinished ...>

bnoordhuis

#include "v8.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <cxxabi.h>
#include <dlfcn.h>

using namespace v8;

bnoordhuis

var fs = require('fs');
var net = require('net');
var http = require('http');
var https = require('https');

var httpAddress = '/path/to/http.sock';
var httpsAddress = '/path/to/https.sock';
fs.unlinkSync(httpAddress);
fs.unlinkSync(httpsAddress);

bnoordhuis

diff --git a/src/node.cc b/src/node.cc
index 32cff12..3c5b616 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -2954,6 +2954,36 @@ static char **copy_argv(int argc, char **argv) {
   return argv_copy;
 }
 
+
+static void OnJitCodeEvent(const JitCodeEvent* event) {

bnoordhuis

#include <stdio.h>
#include <stdlib.h>

#include <sys/syscall.h>
#include <unistd.h>
#include <fcntl.h>

#ifndef SYS___pthread_chdir
# define SYS___pthread_chdir 348
#endif

bnoordhuis

#include "v8.h"
#include <assert.h>
#include <unistd.h>

using namespace v8;

struct WrappedContext
{
  WrappedContext(Handle<Object> obj)
  {

bnoordhuis

#!/usr/bin/env stap

global samples
global all_samples
global timestamp

probe process("node").mark("gc__start")
{
  timestamp = gettimeofday_us()
}

bnoordhuis

for (var a = [], i = 0; i < 64*1024*1024; ++i) a.push(123.456);