ScaleFreeSim.cpp

#include <xrpl/consensus/ConsensusParms.h>
 
#include <csf/PeerGroup.h>
#include <csf/Sim.h>
#include <csf/collectors.h>
#include <csf/random.h>
#include <csf/submitters.h>
#include <csf/timers.h>
#include <gtest/gtest.h>
 
#include <chrono>
#include <iostream>
#include <ostream>
#include <random>
#include <vector>
 
namespace xrpl::test {
 
TEST(ScaleFreeSimTest, DISABLED_scale_free_sim)
{
    using namespace std::chrono;
    using namespace csf;
 
    std::ostream& log = std::cout;
 
    // Generate a quasi-random scale free network and simulate consensus
    // as we vary transaction submission rates
 
    int const n = 100;  // Peers
 
    int const numUNLs = 15;  //  UNL lists
    int const minUNLSize = n / 4, maxUNLSize = n / 2;
 
    ConsensusParms const parms{};
    Sim sim;
    PeerGroup network = sim.createGroup(n);
 
    // generate trust ranks
    std::vector<double> const ranks = sample(network.size(), PowerLawDistribution{1, 3}, sim.rng);
 
    // generate scale-free trust graph
    randomRankedTrust(
        network, ranks, numUNLs, std::uniform_int_distribution<>{minUNLSize, maxUNLSize}, sim.rng);
 
    // nodes with a trust line in either direction are network-connected
    network.connectFromTrust(round<milliseconds>(0.2 * parms.ledgerGRANULARITY));
 
    // Initialize collectors to track statistics to report
    TxCollector txCollector;
    LedgerCollector ledgerCollector;
    auto colls = makeCollectors(txCollector, ledgerCollector);
    sim.collectors.add(colls);
 
    // Initial round to set prior state
    sim.run(1);
 
    // Initialize timers
    HeartbeatTimer heart(sim.scheduler, seconds(10s));
 
    // Run for 10 minutes, submitting 100 tx/second
    std::chrono::nanoseconds const simDuration = 10min;
    std::chrono::nanoseconds const quiet = 10s;
    Rate const rate{.count = 100, .duration = 1000ms};
 
    // txs, start/stop/step, target
    auto peerSelector = makeSelector(network.begin(), network.end(), ranks, sim.rng);
    auto txSubmitter = makeSubmitter(
        ConstantDistribution{rate.inv()},
        sim.scheduler.now() + quiet,
        sim.scheduler.now() + (simDuration - quiet),
        peerSelector,
        sim.scheduler,
        sim.rng);
 
    // run simulation for given duration
    heart.start();
    sim.run(simDuration);
 
    EXPECT_TRUE(sim.branches() == 1);
    EXPECT_TRUE(sim.synchronized());
 
    // TODO: Clean up this formatting mess!!
 
    log << "Peers: " << network.size() << std::endl;
    log << "Simulated Duration: " << duration_cast<milliseconds>(simDuration).count() << " ms"
        << std::endl;
    log << "Branches: " << sim.branches() << std::endl;
    log << "Synchronized: " << (sim.synchronized() ? "Y" : "N") << std::endl;
    log << std::endl;
 
    txCollector.report(simDuration, log);
    ledgerCollector.report(simDuration, log);
    // Print summary?
    // # forks?  # of LCLs?
    // # peers
    // # tx submitted
    // # ledgers/sec etc.?
}
 
}  // namespace xrpl::test