storage: add Benchmarks for ScrapeSwarm, optimize implementations

storage/memory/peer_store.go

@@ -518,13 +518,14 @@ func (ps *peerStore) ScrapeSwarm(ih bittorrent.InfoHash, addressFamily bittorren
 	shard := ps.shards[ps.shardIndex(ih, addressFamily)]
 	shard.RLock()
 
-	if _, ok := shard.swarms[ih]; !ok {
+	swarm, ok := shard.swarms[ih]
+	if !ok {
 		shard.RUnlock()
 		return
 	}
 
-	resp.Incomplete = uint32(len(shard.swarms[ih].leechers))
+	resp.Incomplete = uint32(len(swarm.leechers))
-	resp.Complete = uint32(len(shard.swarms[ih].seeders))
+	resp.Complete = uint32(len(swarm.seeders))
 	shard.RUnlock()
 
 	return

storage/memory/peer_store_test.go

@@ -18,6 +18,7 @@ func createNew() s.PeerStore {
 
 func TestPeerStore(t *testing.T) { s.TestPeerStore(t, createNew()) }
 
+func BenchmarkNop(b *testing.B)                        { s.Nop(b, createNew()) }
 func BenchmarkPut(b *testing.B)                        { s.Put(b, createNew()) }
 func BenchmarkPut1k(b *testing.B)                      { s.Put1k(b, createNew()) }
 func BenchmarkPut1kInfohash(b *testing.B)              { s.Put1kInfohash(b, createNew()) }
@@ -42,3 +43,5 @@ func BenchmarkAnnounceLeecher(b *testing.B)            { s.AnnounceLeecher(b, cr
 func BenchmarkAnnounceLeecher1kInfohash(b *testing.B)  { s.AnnounceLeecher1kInfohash(b, createNew()) }
 func BenchmarkAnnounceSeeder(b *testing.B)             { s.AnnounceSeeder(b, createNew()) }
 func BenchmarkAnnounceSeeder1kInfohash(b *testing.B)   { s.AnnounceSeeder1kInfohash(b, createNew()) }
+func BenchmarkScrapeSwarm(b *testing.B)                { s.ScrapeSwarm(b, createNew()) }
+func BenchmarkScrapeSwarm1kInfohash(b *testing.B)      { s.ScrapeSwarm1kInfohash(b, createNew()) }

storage/memorybysubnet/peer_store.go

@@ -643,13 +643,14 @@ func (ps *peerStore) ScrapeSwarm(ih bittorrent.InfoHash, addressFamily bittorren
 	shard := ps.shards[ps.shardIndex(ih, addressFamily)]
 	shard.RLock()
 
-	if _, ok := shard.swarms[ih]; !ok {
+	swarm, ok := shard.swarms[ih]
+	if !ok {
 		shard.RUnlock()
 		return
 	}
 
-	resp.Incomplete = uint32(shard.swarms[ih].lenLeechers())
+	resp.Incomplete = uint32(swarm.lenLeechers())
-	resp.Complete = uint32(shard.swarms[ih].lenSeeders())
+	resp.Complete = uint32(swarm.lenSeeders())
 	shard.RUnlock()
 
 	return

storage/memorybysubnet/peer_store_test.go

@@ -23,6 +23,7 @@ func createNew() s.PeerStore {
 
 func TestPeerStore(t *testing.T) { s.TestPeerStore(t, createNew()) }
 
+func BenchmarkNop(b *testing.B)                        { s.Nop(b, createNew()) }
 func BenchmarkPut(b *testing.B)                        { s.Put(b, createNew()) }
 func BenchmarkPut1k(b *testing.B)                      { s.Put1k(b, createNew()) }
 func BenchmarkPut1kInfohash(b *testing.B)              { s.Put1kInfohash(b, createNew()) }
@@ -47,3 +48,5 @@ func BenchmarkAnnounceLeecher(b *testing.B)            { s.AnnounceLeecher(b, cr
 func BenchmarkAnnounceLeecher1kInfohash(b *testing.B)  { s.AnnounceLeecher1kInfohash(b, createNew()) }
 func BenchmarkAnnounceSeeder(b *testing.B)             { s.AnnounceSeeder(b, createNew()) }
 func BenchmarkAnnounceSeeder1kInfohash(b *testing.B)   { s.AnnounceSeeder1kInfohash(b, createNew()) }
+func BenchmarkScrapeSwarm(b *testing.B)                { s.ScrapeSwarm(b, createNew()) }
+func BenchmarkScrapeSwarm1kInfohash(b *testing.B)      { s.ScrapeSwarm1kInfohash(b, createNew()) }

storage/storage_bench.go

@@ -95,6 +95,19 @@ func runBenchmark(b *testing.B, ps PeerStore, parallel bool, sf setupFunc, ef ex
 	}
 }
 
+// Nop executes a no-op for each iteration.
+// It should produce the same results for each PeerStore.
+// This can be used to get an estimate of the impact of the benchmark harness
+// on benchmark results and an estimate of the general performance of the system
+// benchmarked on.
+//
+// Nop can run in parallel.
+func Nop(b *testing.B, ps PeerStore) {
+	runBenchmark(b, ps, true, putPeers, func(i int, ps PeerStore, bd *benchData) error {
+		return nil
+	})
+}
+
 // Put benchmarks the PutSeeder method of a PeerStore by repeatedly Putting the
 // same Peer for the same InfoHash.
 //
@@ -415,3 +428,24 @@ func AnnounceSeeder1kInfohash(b *testing.B, ps PeerStore) {
 		return err
 	})
 }
+
+// ScrapeSwarm benchmarks the ScrapeSwarm method of a PeerStore.
+// The swarm scraped has 500 seeders and 500 leechers.
+//
+// ScrapeSwarm can run in parallel.
+func ScrapeSwarm(b *testing.B, ps PeerStore) {
+	runBenchmark(b, ps, true, putPeers, func(i int, ps PeerStore, bd *benchData) error {
+		ps.ScrapeSwarm(bd.infohashes[0], bittorrent.IPv4)
+		return nil
+	})
+}
+
+// ScrapeSwarm1kInfohash behaves like ScrapeSwarm with one of 1000 infohashes.
+//
+// ScrapeSwarm1kInfohash can run in parallel.
+func ScrapeSwarm1kInfohash(b *testing.B, ps PeerStore) {
+	runBenchmark(b, ps, true, putPeers, func(i int, ps PeerStore, bd *benchData) error {
+		ps.ScrapeSwarm(bd.infohashes[i%1000], bittorrent.IPv4)
+		return nil
+	})
+}