Function lockMemoryResident

app/src/Platform/AppPlatform.cpp:579–611

* @brief Pins @p len bytes at @p ptr into physical memory (best effort): page-fault stalls on * the frame-scan buffers become latency spikes at rate. Returns true when pinned. */

 *        the frame-scan buffers become latency spikes at rate. Returns true when pinned.
 */
bool lockMemoryResident(const void* ptr, size_t len)
{
  Q_ASSERT(ptr != nullptr);
  Q_ASSERT(len > 0);

  if (!ptr || len == 0) [[unlikely]]
    return false;

#if defined(Q_OS_WIN)
  void* base = const_cast<void*>(ptr);
  if (VirtualLock(base, len))
    return true;

  SIZE_T minWs = 0;
  SIZE_T maxWs = 0;
  if (!GetProcessWorkingSetSize(GetCurrentProcess(), &minWs, &maxWs))
    return false;

  const SIZE_T slack  = 2u * 1024u * 1024u;
  const SIZE_T newMin = minWs + len + slack;
  const SIZE_T newMax = (maxWs > newMin + slack) ? maxWs : (newMin + slack);
  if (!SetProcessWorkingSetSize(GetCurrentProcess(), newMin, newMax))
    return false;

  return VirtualLock(base, len) != 0;
#elif defined(Q_OS_LINUX) || defined(Q_OS_MACOS)
  return mlock(ptr, len) == 0;
#else
  Q_UNUSED(ptr);
  Q_UNUSED(len);
  return false;
#endif
}

/**
 * @brief Registers the calling (ingest/main) thread with MMCSS "Pro Audio"; call only after the