Add performance benchmark suite.

Package.swift

@@ -34,6 +34,7 @@ let package = Package(
         .target(name: "NIOSSH", dependencies: ["NIO", "NIOFoundationCompat", "Crypto"]),
         .target(name: "NIOSSHClient", dependencies: ["NIO", "NIOSSH", "NIOConcurrencyHelpers"]),
         .target(name: "NIOSSHServer", dependencies: ["NIO", "NIOSSH", "NIOFoundationCompat", "Crypto"]),
+        .target(name: "NIOSSHPerformanceTester", dependencies: ["NIO", "NIOSSH", "Crypto"]),
         .testTarget(name: "NIOSSHTests", dependencies: ["NIOSSH", "NIO", "NIOFoundationCompat"]),
     ]
 )

Sources/NIOSSHPerformanceTester/Benchmark.swift

@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2020 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+protocol Benchmark: AnyObject {
+    func setUp() throws
+    func tearDown()
+    func run() throws -> Int
+}
+
+func measureAndPrint<B: Benchmark>(desc: String, benchmark bench: B) throws {
+    try bench.setUp()
+    defer {
+        bench.tearDown()
+    }
+    try measureAndPrint(desc: desc) {
+        try bench.run()
+    }
+}

Sources/NIOSSHPerformanceTester/BenchmarkHandshake.swift

@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2020 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+import Crypto
+import NIO
+import NIOSSH
+
+final class BenchmarkHandshake: Benchmark {
+    let serverRole = SSHConnectionRole.server(.init(hostKeys: [.init(ed25519Key: .init())], userAuthDelegate: ExpectPasswordDelegate("password")))
+    let clientRole = SSHConnectionRole.client(.init(userAuthDelegate: RepeatingPasswordDelegate("password")))
+    let loopCount: Int
+
+    init(loopCount: Int) {
+        self.loopCount = loopCount
+    }
+
+    func setUp() throws {}
+
+    func tearDown() {}
+
+    func run() throws -> Int {
+        for _ in 0 ..< self.loopCount {
+            let b2b = BackToBackEmbeddedChannel()
+            b2b.client.connect(to: try .init(unixDomainSocketPath: "/foo"), promise: nil)
+            b2b.server.connect(to: try .init(unixDomainSocketPath: "/foo"), promise: nil)
+
+            try b2b.client.pipeline.addHandler(NIOSSHHandler(role: self.clientRole, allocator: b2b.client.allocator, inboundChildChannelInitializer: nil)).wait()
+            try b2b.server.pipeline.addHandler(NIOSSHHandler(role: self.serverRole, allocator: b2b.server.allocator, inboundChildChannelInitializer: nil)).wait()
+            try b2b.interactInMemory()
+        }
+
+        return self.loopCount
+    }
+}

Sources/NIOSSHPerformanceTester/main.swift

@@ -0,0 +1,63 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2020 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Crypto
+import Dispatch
+import Foundation
+import NIO
+import NIOSSH
+
+// MARK: Test Harness
+
+var warning: String = ""
+assert({
+    print("======================================================")
+    print("= YOU ARE RUNNING NIOPerformanceTester IN DEBUG MODE =")
+    print("======================================================")
+    warning = " <<< DEBUG MODE >>>"
+    return true
+}())
+
+public func measure(_ fn: () throws -> Int) rethrows -> [TimeInterval] {
+    func measureOne(_ fn: () throws -> Int) rethrows -> TimeInterval {
+        let start = Date()
+        _ = try fn()
+        let end = Date()
+        return end.timeIntervalSince(start)
+    }
+
+    _ = try measureOne(fn) /* pre-heat and throw away */
+    var measurements = Array(repeating: 0.0, count: 10)
+    for i in 0 ..< 10 {
+        measurements[i] = try measureOne(fn)
+    }
+
+    return measurements
+}
+
+let limitSet = CommandLine.arguments.dropFirst()
+
+public func measureAndPrint(desc: String, fn: () throws -> Int) rethrows {
+    if limitSet.count == 0 || limitSet.contains(desc) {
+        print("measuring\(warning): \(desc): ", terminator: "")
+        let measurements = try measure(fn)
+        print(measurements.reduce("") { $0 + "\($1), " })
+    } else {
+        print("skipping '\(desc)', limit set = \(limitSet)")
+    }
+}
+
+// MARK: Utilities
+
+try measureAndPrint(desc: "10000_handshakes", benchmark: BenchmarkHandshake(loopCount: 10000))

Sources/NIOSSHPerformanceTester/shared.swift

@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2020 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+import Crypto
+import NIO
+import NIOSSH
+
+class BackToBackEmbeddedChannel {
+    private(set) var client: EmbeddedChannel
+    private(set) var server: EmbeddedChannel
+    private var loop: EmbeddedEventLoop
+
+    init() {
+        self.loop = EmbeddedEventLoop()
+        self.client = EmbeddedChannel(loop: self.loop)
+        self.server = EmbeddedChannel(loop: self.loop)
+    }
+
+    func run() {
+        self.loop.run()
+    }
+
+    func interactInMemory() throws {
+        var workToDo = true
+
+        while workToDo {
+            workToDo = false
+
+            self.loop.run()
+            let clientDatum = try self.client.readOutbound(as: IOData.self)
+            let serverDatum = try self.server.readOutbound(as: IOData.self)
+
+            if let clientMsg = clientDatum {
+                try self.server.writeInbound(clientMsg)
+                workToDo = true
+            }
+
+            if let serverMsg = serverDatum {
+                try self.client.writeInbound(serverMsg)
+                workToDo = true
+            }
+        }
+    }
+}
+
+final class ExpectPasswordDelegate: NIOSSHServerUserAuthenticationDelegate {
+    let supportedAuthenticationMethods: NIOSSHAvailableUserAuthenticationMethods = .password
+
+    let expectedPassword: String
+
+    init(_ expectedPassword: String) {
+        self.expectedPassword = expectedPassword
+    }
+
+    func requestReceived(request: NIOSSHUserAuthenticationRequest, responsePromise: EventLoopPromise<NIOSSHUserAuthenticationOutcome>) {
+        guard case .password(let password) = request.request, password.password == self.expectedPassword else {
+            responsePromise.succeed(.failure)
+            return
+        }
+        responsePromise.succeed(.success)
+    }
+}
+
+final class RepeatingPasswordDelegate: NIOSSHClientUserAuthenticationDelegate {
+    let password: String
+
+    init(_ password: String) {
+        self.password = password
+    }
+
+    func nextAuthenticationType(availableMethods: NIOSSHAvailableUserAuthenticationMethods, nextChallengePromise: EventLoopPromise<NIOSSHUserAuthenticationOffer?>) {
+        if availableMethods.contains(.password) {
+            nextChallengePromise.succeed(.init(username: "foo", serviceName: "ssh-connection", offer: .password(.init(password: self.password))))
+        } else {
+            nextChallengePromise.succeed(nil)
+        }
+    }
+}