config.hpp

/* SPDX-License-Identifier: MPL-2.0 */

#ifndef __ZMQ_CONFIG_HPP_INCLUDED__
#define __ZMQ_CONFIG_HPP_INCLUDED__

namespace zmq
{
//  Compile-time settings.

enum
{
    //  Number of new messages in message pipe needed to trigger new memory
    //  allocation. Setting this parameter to 256 decreases the impact of
    //  memory allocation by approximately 99.6%
    message_pipe_granularity = 256,

    //  Commands in pipe per allocation event.
    command_pipe_granularity = 16,

    //  Determines how often does socket poll for new commands when it
    //  still has unprocessed messages to handle. Thus, if it is set to 100,
    //  socket will process 100 inbound messages before doing the poll.
    //  If there are no unprocessed messages available, poll is done
    //  immediately. Decreasing the value trades overall latency for more
    //  real-time behaviour (less latency peaks).
    inbound_poll_rate = 100,

    //  Maximal delta between high and low watermark.
    max_wm_delta = 1024,

    //  Maximum number of events the I/O thread can process in one go.
    max_io_events = 256,

    //  Maximal batch size of packets forwarded by a ZMQ proxy.
    //  Increasing this value improves throughput at the expense of
    //  latency and fairness.
    proxy_burst_size = 1000,

    //  Maximal delay to process command in API thread (in CPU ticks).
    //  3,000,000 ticks equals to 1 - 2 milliseconds on current CPUs.
    //  Note that delay is only applied when there is continuous stream of
    //  messages to process. If not so, commands are processed immediately.
    max_command_delay = 3000000,

    //  Low-precision clock precision in CPU ticks. 1ms. Value of 1000000
    //  should be OK for CPU frequencies above 1GHz. If should work
    //  reasonably well for CPU frequencies above 500MHz. For lower CPU
    //  frequencies you may consider lowering this value to get best
    //  possible latencies.
    clock_precision = 1000000,

    //  On some OSes the signaler has to be emulated using a TCP
    //  connection. In such cases following port is used.
    //  If 0, it lets the OS choose a free port without requiring use of a
    //  global mutex. The original implementation of a Windows signaler
    //  socket used port 5905 instead of letting the OS choose a free port.
    //  https://github.com/zeromq/libzmq/issues/1542
    signaler_port = 0
};
}

#endif