Redesign CSF framework (RIPD-1361):

- Separate `Scheduler` from `BasicNetwork`.
- Add an event/collector framework for monitoring invariants and calculating statistics.
- Allow distinct network and trust connections between Peers.
- Add a simple routing strategy to support broadcasting arbitrary messages.
- Add a common directed graph (`Digraph`) class for representing network and trust topologies.
- Add a `PeerGroup` class for simpler specification of the trust and network topologies.
- Add a `LedgerOracle` class to ensure distinct ledger histories and simplify branch checking.
- Add a `Submitter` to send transactions in at fixed or random intervals to fixed or random peers.

Co-authored-by: Joseph McGee

src/test/consensus/ScaleFreeSim_test.cpp

@@ -0,0 +1,123 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012-2016 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+#include <BeastConfig.h>
+#include <ripple/beast/clock/manual_clock.h>
+#include <ripple/beast/unit_test.h>
+#include <test/csf.h>
+#include <test/csf/random.h>
+#include <utility>
+
+namespace ripple {
+namespace test {
+
+class ScaleFreeSim_test : public beast::unit_test::suite
+{
+    void
+    run() override
+    {
+        using namespace std::chrono;
+        using namespace csf;
+
+        // 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 minues, submitting 100 tx/second
+        std::chrono::nanoseconds const simDuration = 10min;
+        std::chrono::nanoseconds const quiet = 10s;
+        Rate const rate{100, 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);
+
+        BEAST_EXPECT(sim.branches() == 1);
+        BEAST_EXPECT(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.?
+    }
+};
+
+BEAST_DEFINE_TESTSUITE_MANUAL(ScaleFreeSim, consensus, ripple);
+
+}  // namespace test
+}  // namespace ripple