[buffers]
max_workers=16
On Windows NT familiy operating systems DP4 now creates "worker threads" to perform I/O operations that are likely to be slow and synchronous. By default it uses 16 worker threads. In fact most of the time most of these threads are idle - they exist only to ensure that disk read and write operations are asynchronous (Windows reserves the right to make disk I/O synchronous even when an asynchronous API is used, and often does so).
If your system is very heavily loaded you may find it becomes generally unresponsive, because DP4 is consuming too much of its resources. You can reduce this effect, at the cost of adversely impacting DP4 performance, by limiting the number of worker threads. The minimum permitted value of max_workers is 2.