Robotics Service Bus

A mail is sent to the spread list with this program:

//============================================================================
// Name        : spreadtest.cpp
// Author      : Johannes Wienke
// Version     :
// Copyright   : 2011, CoR-Lab, Bielefeld University
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <algorithm>
#include <iostream>
#include <string>

#include <assert.h>
#include <string.h>
#include <sys/time.h>
#include <time.h>

#include <boost/cstdint.hpp>
#include <boost/thread.hpp>
#include <boost/bind.hpp>

#include <sp.h>

using namespace std;

char randAlnumChar() {
    char c;
    do {
        c = (char) (rand() % ('z' - '0' + 1) + '0');
    } while (!std::isalnum(c));
    return c;
}

std::string randAlnumStr(const std::string::size_type &length) {
    std::string s;
    s.reserve(length);
    generate_n(std::back_inserter(s), length, randAlnumChar);
    return s;
}

void currentTimeMicros(boost::uint64_t &result) {

    timeval tv;
    gettimeofday(&tv, NULL);

    // (second-value in microseconds) + (microsecond value)
    result = (((boost::uint64_t) tv.tv_sec) * 1000000ull) + (tv.tv_usec);

}

unsigned int numMessages = 1000;
unsigned int dataLength = 100000;

void sender() {

    char privateGroup[MAX_PRIVATE_NAME + 1000];
    mailbox sendMbox;
    int connected = SP_connect("4803", 0, 0, false, &sendMbox, privateGroup);
    assert(connected == ACCEPT_SESSION);

    string groupName = "foo";

    // first send some messages
    string data = randAlnumStr(dataLength);
    for (unsigned int i = 0; i < numMessages; ++i) {
        int sent = SP_multicast(sendMbox, RELIABLE_MESS, groupName.c_str(), 0,
                strlen(data.c_str()) + 1, data.c_str());
        assert(sent >= 0);
    }

    int disconnected = SP_disconnect(sendMbox);
    assert(disconnected == 0);
    cout << "##### disconnected!" << endl;

}

int main() {

    boost::thread senderThread(&sender);

    char privateGroup[MAX_PRIVATE_NAME];
    mailbox receiveMbox;
    int connected = SP_connect("4803", 0, 0, false, &receiveMbox, privateGroup);
    assert(connected == ACCEPT_SESSION);

    string groupName = "foo";
    SP_join(receiveMbox, groupName.c_str());

    // then receive them
    service service;
    char sender[MAX_GROUP_NAME];
    int maxGroups = 10;
    int numGroups = 0;
    char groups[maxGroups][MAX_GROUP_NAME];
    short int messageType;
    int endian;
    char message[dataLength + 10];
    boost::uint64_t before;
    boost::uint64_t after;
    for (unsigned int i = 0; i < numMessages; ++i) {
        currentTimeMicros(before);
        int size = SP_receive(receiveMbox, &service, sender, maxGroups,
                &numGroups, groups, &messageType, &endian, dataLength + 10,
                message);
        currentTimeMicros(after);
        cout << "receive took " << (after - before) << " us" << endl;
        assert(size >= 0);
        boost::this_thread::sleep(boost::posix_time::milliseconds(1));
    }

    cout << "received messages" << endl;

    // leave group, disconnect mailboxes
    int left = SP_leave(receiveMbox, groupName.c_str());
    assert(left == 0);
    int disconnected = SP_disconnect(receiveMbox);
    assert(disconnected == 0);

    senderThread.join();

    return 0;

}

As the spread website and mailing list are still completely inaccessible, I will remove this ticket from the version 0.3. It will be resolved when there is contact to the spread community again.

Finally sent to the list...

There is no reply from the list since weeks. I will more or less close this right now as I do not feel that I have time ton investigate in this. This is the list thread: http://lists.spread.org/pipermail/spread-users/2011-August/thread.html#4462

Another reply:

Johannes,

In the new version of Spread we are currently developing we believe we've solved this issue. Spread will now use both the old badger timeout semantics and also monitor client sockets for write-ability. So, the issue you saw should no longer exist in the next version of Spread which is due out soon.

Cheers!

I mark this as resolved as we have an upstream fix now.