Anyone have any idea why apps are starting to search /proc/sys/vm?

[Jerry James]

On Sat, Oct 6, 2012 at 5:44 AM, Daniel J Walsh <dwalsh at redhat.com> wrote:
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> https://bugzilla.redhat.com/show_bug.cgi?id=863258
> https://bugzilla.redhat.com/show_bug.cgi?id=863257
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Perhaps this glibc code (in sysdeps/unix/sysv/linux/malloc-sysdep.h)?

static inline bool
check_may_shrink_heap (void)
{
  static int may_shrink_heap = -1;

  if (__builtin_expect (may_shrink_heap >= 0, 1))
    return may_shrink_heap;

  may_shrink_heap = __libc_enable_secure;

  if (__builtin_expect (may_shrink_heap == 0, 1))
    {
      int fd = open_not_cancel_2 ("/proc/sys/vm/overcommit_memory",
                                  O_RDONLY | O_CLOEXEC);
      if (fd >= 0)
        {
          char val;
          ssize_t n = read_not_cancel (fd, &val, 1);
          may_shrink_heap = n > 0 && val == '2';
          close_not_cancel_no_status (fd);
        }
    }

  return may_shrink_heap;
}

-- 
Jerry James
http://www.jamezone.org/