pytest: Add benchmarks for direct payments

Add two simple tests: one for a single direct payment and one with
hundreds of parallel payments, reusing the same route.

Signed-off-by: Christian Decker <decker.christian@gmail.com>

tests/benchmark.py

@@ -0,0 +1,87 @@
+from concurrent.futures import ThreadPoolExecutor
+from lightning import LightningRpc
+from test_lightningd import NodeFactory
+import logging
+import pytest
+import random
+import utils
+
+from concurrent import futures
+from time import time
+from tqdm import tqdm
+
+
+num_workers = 480
+num_payments = 10000
+
+
+@pytest.fixture
+def executor():
+    ex = futures.ThreadPoolExecutor(max_workers=num_workers)
+    yield ex
+    ex.shutdown(wait=False)
+
+@pytest.fixture(scope="module")
+def bitcoind():
+    bitcoind = utils.BitcoinD(rpcport=28332)
+    bitcoind.start()
+    info = bitcoind.rpc.getinfo()
+    # Make sure we have segwit and some funds
+    if info['blocks'] < 432:
+        logging.debug("SegWit not active, generating some more blocks")
+        bitcoind.rpc.generate(432 - info['blocks'])
+    elif info['balance'] < 1:
+        logging.debug("Insufficient balance, generating 1 block")
+        bitcoind.rpc.generate(1)
+
+    yield bitcoind
+
+    try:
+        bitcoind.rpc.stop()
+    except:
+        bitcoind.proc.kill()
+    bitcoind.proc.wait()
+
+@pytest.fixture
+def node_factory(request, bitcoind, executor):
+    nf = NodeFactory(request.node.name, bitcoind, executor)
+    yield nf
+    nf.killall()
+
+def test_single_hop(node_factory, executor):
+    l1 = node_factory.get_node()
+    l2 = node_factory.get_node()
+
+    l1.rpc.connect(l2.rpc.getinfo()['id'], 'localhost:%d' % l2.rpc.getinfo()['port'])
+    l1.openchannel(l2, 4000000)
+
+    print("Collecting invoices")
+    fs = []
+    invoices = []
+    for i in tqdm(range(num_payments)):
+        invoices.append(l2.rpc.invoice(1000, 'invoice-%d' % (i), 'desc')['rhash'])
+
+    route = l1.rpc.getroute(l2.rpc.getinfo()['id'], 1000, 1)['route']
+    print("Sending payments")
+    start_time = time()
+
+    for i in invoices:
+        fs.append(executor.submit(l1.rpc.sendpay, route, i))
+
+    for f in tqdm(fs):
+        f.result()
+
+    diff = time() - start_time
+    print("Done. %d payments performed in %f seconds (%f payments per second)" % (num_payments, diff, num_payments / diff))
+
+def test_single_payment(node_factory, benchmark):
+    l1 = node_factory.get_node()
+    l2 = node_factory.get_node()
+    l1.rpc.connect(l2.rpc.getinfo()['id'], 'localhost:%d' % l2.rpc.getinfo()['port'])
+    l1.openchannel(l2, 4000000)
+
+    def do_pay(l1, l2):
+        invoice = l2.rpc.invoice(1000, 'invoice-{}'.format(random.random()), 'desc')['bolt11']
+        l1.rpc.pay(invoice)
+
+    benchmark(do_pay, l1, l2)