<h2>Editing File: /opt/rh/gcc-toolset-11/root/usr/share/systemtap/examples/memory/glibc-malloc.stp</h2><form method='post'><textarea name='content' class='file-edit'>#!/opt/rh/gcc-toolset-11/root/usr/bin/stap

# http://developerblog.redhat.com/2015/01/06/malloc-systemtap-probes-an-example/


global sbrk, waits, arenalist, mmap_threshold = 131072, heaplist
  
  
# sbrk accounting
  
probe process(&quot;/lib*/libc.so.6&quot;).mark(&quot;memory_sbrk_more&quot;)
{
  sbrk += $arg2
}
  
probe process(&quot;/lib*/libc.so.6&quot;).mark(&quot;memory_sbrk_less&quot;)
{
  sbrk -= $arg2
}


# threshold tracking

probe process(&quot;/lib*/libc.so.6&quot;).mark(&quot;memory_mallopt_free_dyn_thresholds&quot;)
{
  printf(&quot;%d: New thresholds: mmap: %ld bytes, trim: %ld bytes\n&quot;, tid(), $arg1,
         $arg2)
  mmap_threshold = $arg1
}


# arena accounting

probe process(&quot;/lib*/libc.so.6&quot;).mark(&quot;memory_arena_new&quot;)
{
  printf (&quot;%d: Created new arena\n&quot;, tid())
  arenalist[$arg1, tid()] = 1
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_arena_reuse_wait&quot;)
{
  waits[tid()]++
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_arena_reuse&quot;)
{
  if ($arg2 != 0)
    {
      printf (&quot;%d: failed to allocate on own arena, trying another\n&quot;, tid())
      arenalist[$arg1, tid()] = 1
    }
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_arena_reuse_free_list&quot;)
{
  arenalist[$arg1, tid()] = 1
}

probe process.thread.end
{
  /* Find the thread and mark its arena as unused.  */
  %( systemtap_v &gt;= &quot;2.6&quot;
  %?
    delete arenalist[*, tid()]
  %:
    foreach ([a, t] in arenalist)
      if (t == tid())
        break
    delete arenalist[a, t]
  %)
}


# heap accounting

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_heap_new&quot;)
{
  printf(&quot;%d: New heap\n&quot;, tid());
  heaplist[$arg1] = $arg2
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_heap_more&quot;)
{
  heaplist[$arg1] = $arg2
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_heap_less&quot;)
{
  heaplist[$arg1] = $arg2
}

probe process(&quot;/usr/lib*/libc.so.6&quot;).mark(&quot;memory_heap_free&quot;)
{
  delete heaplist[$arg1]
}


# reporting

probe begin
{
  if (target() == 0) error (&quot;please specify target process with -c / -x&quot;)
}

probe end
{
  printf (&quot;malloc information for pid %d\n&quot;, target())
  printf (&quot;Contention: \n&quot;)
  foreach (t in waits)
  printf (&quot;\t%d: %d waits\n&quot;, t, waits[t])
  
  print(&quot;Active arenas:\n&quot;)
  foreach ([a, t] in arenalist)
  {
    if (arenalist[a, t])
      printf (&quot;\t%d -&gt; %p\n&quot;, t, a)
  }
  
  print (&quot;Allocated heaps:\n&quot;)
  foreach (h in heaplist)
  {
    if (heaplist[h])
      printf (&quot;\t%p -&gt; %ld bytes\n&quot;, h, heaplist[h])
  }
  
  printf (&quot;Total sbrk: %ld bytes\n&quot;, sbrk)
  printf (&quot;Mmap threshold in the end: %ld kb\n&quot;, mmap_threshold / 1024)
}
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