Full Scroll Performance Framework

ButtonScrollPerformanceTest.m

/*
The MIT License

Copyright (c) 2010-2018 Google, Inc. http://angularjs.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#import <XCTest/XCTest.h>
#import <KIF/KIF.h>

#import "KSScrollPerformanceDetector.h"
#import "usage.h"

// This is specifically chosen to be the right speed to not trigger optimizations
static const CGFloat KSScrollPerformanceTestsVelocity = -0.15f;

@interface ButtonScrollPerformanceTests : KIFTestCase <KSScrollPerformanceDetectorDelegate>

@property(nonatomic, assign, readwrite) NSInteger droppedFramesLimit;
@property(nonatomic, assign, readwrite) NSInteger frameDropEventsLimit;
@property(nonatomic, strong, nonnull) KSScrollPerformanceDetector *scrollPerformanceDetector;
@property(nonatomic, strong, nonnull) UITableView *tableView;

@end

@implementation ButtonScrollPerformanceTests

- (void)beforeEach {
    self.scrollPerformanceDetector = [[KSScrollPerformanceDetector alloc] init];
    self.scrollPerformanceDetector.delegate = self;
    self.droppedFramesLimit = 3;
    self.frameDropEventsLimit = 3;
}

- (void)setUp {
    [super setUp];
    // Put setup code here. This method is called before the invocation of each test method in the class.
    self.continueAfterFailure = YES;
}

- (void)testButtonPerformance {
    [tester tapViewWithAccessibilityLabel:@"Button"];
    [tester tapViewWithAccessibilityLabel:@"Performance"];
    [self scrollTableToEndWithIdentifier:@"performance-test-table"];
}

- (void)scrollTableToEndWithIdentifier:(NSString *)accessibilityIdentifier {
    UITableView *tableView;
    [tester waitForAccessibilityElement:NULL view:&tableView withIdentifier:accessibilityIdentifier tappable:NO];
    self.tableView = tableView;
    NSIndexPath *lastIndexPath = [NSIndexPath indexPathForRow:[self.tableView numberOfRowsInSection:0] - 1 inSection:0];
    NSArray<NSIndexPath *> *visibleIndexPaths = [self.tableView indexPathsForVisibleRows];

    [self.scrollPerformanceDetector resume];
    while (![visibleIndexPaths containsObject:lastIndexPath]) {
        [tester scrollViewWithAccessibilityIdentifier:accessibilityIdentifier byFractionOfSizeHorizontal:0.0f vertical:KSScrollPerformanceTestsVelocity];
        visibleIndexPaths = [self.tableView indexPathsForVisibleRows];
        [self.scrollPerformanceDetector clearFrameDropCount];
    }
    [self.scrollPerformanceDetector pause];
}

- (void)framesDropped:(NSInteger)framesDroppedCount cumulativeFramesDropped:(NSInteger)cumulativeFramesDropped cumulativeFrameDropEvents:(NSInteger)cumulativeFrameDropEvents {
    if (framesDroppedCount >= self.droppedFramesLimit) {
        XCTFail(@"Past limit for number of dropped frames");
    }

    if (cumulativeFrameDropEvents >= self.frameDropEventsLimit) {
        XCTFail(@"Past limit for number of frame drop events");
    }
}

@end

KSScrollPerformanceDetector.h

/*
The MIT License

Copyright (c) 2010-2018 Google, Inc. http://angularjs.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#import <Foundation/Foundation.h>

/**
 These methods will not be called on the main thread. So,
 if you will be doing anything with UIKit, ensure you dispatch back
 to the main thread.
 */
@protocol KSScrollPerformanceDetectorDelegate<NSObject>
@optional
- (void)framesDropped:(NSInteger)framesDroppedCount cumulativeFramesDropped:(NSInteger)cumulativeFramesDropped cumulativeFrameDropEvents:(NSInteger)cumulativeFrameDropEvents;
@end


@interface KSScrollPerformanceDetector : NSObject

@property(nonatomic, assign, readonly) NSInteger currentFrameDropCount;
@property(nonatomic, assign, readonly) NSInteger currentFrameDropEventCount;
@property(nonatomic, weak, nullable) id<KSScrollPerformanceDetectorDelegate> delegate;

- (nonnull instancetype)init NS_DESIGNATED_INITIALIZER;
- (void)resume;
- (void)pause;
- (void)clearFrameDropCount;

@end

KSScrollPerformanceDetector.m

/*
The MIT License

Copyright (c) 2010-2018 Google, Inc. http://angularjs.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#import "KSScrollPerformanceDetector.h"
#import <UIKit/UIKit.h>

@interface KSScrollPerformanceDetector()

@property(nonatomic, strong, nonnull) CADisplayLink *displayLink;
@property(nonatomic, assign, readwrite) CFTimeInterval lastTimestamp;
@property(nonatomic, assign, readwrite) NSInteger currentFrameDropCount;
@property(nonatomic, assign, readwrite) NSInteger currentFrameDropEventCount;
@property(nonatomic, strong, nonnull) dispatch_queue_t workerQueue;

- (void)displayLinkTriggered:(CADisplayLink *)sender;
- (void)calculateFrameDropForNumberOfFrames:(NSInteger)numberOfFrames;
- (void)registerLifecyleNotifications;

@end

@implementation KSScrollPerformanceDetector

#pragma mark - Initializers

- (instancetype)init {
    self = [super init];
    [self registerLifecyleNotifications];
    _displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(displayLinkTriggered:)];
    _displayLink.paused = YES;
    [_displayLink addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
    _lastTimestamp = 0;
    dispatch_queue_attr_t attributes = dispatch_queue_attr_make_with_qos_class(DISPATCH_QUEUE_SERIAL, QOS_CLASS_USER_INITIATED, DISPATCH_QUEUE_PRIORITY_HIGH);
    _workerQueue = dispatch_queue_create("com.frame-rate-reporter.worker", attributes);
    return self;
}

#pragma mark - Public Methods

- (void)clearFrameDropCount {
    __weak typeof(self) weakSelf = self;
    dispatch_async(self.workerQueue, ^{
        typeof(self) strongSelf = weakSelf;
        if (!strongSelf) {
            return;
        }
        self->_currentFrameDropCount = 0;
        self->_currentFrameDropEventCount = 0;
    });
}

- (void)resume {
    self.displayLink.paused = NO;
}

- (void)pause {
    self.displayLink.paused = YES;
}

#pragma mark - Private Methods

#pragma mark Lifecyle

- (void)registerLifecyleNotifications {
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(notifyActivate:)
                                                 name:UIApplicationDidBecomeActiveNotification
                                               object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(notifyDeactivate:)
                                                 name:UIApplicationWillResignActiveNotification
                                               object:nil];
}

- (void)notifyActivate:(NSNotification *)notification {
    self.displayLink.paused = NO;
    self.lastTimestamp = 0;
}

- (void)notifyDeactivate:(NSNotification *)notification {
    self.displayLink.paused = YES;
}

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    self.displayLink.paused = YES;
    [self.displayLink invalidate];
}

#pragma mark Calculations

- (void)displayLinkTriggered:(CADisplayLink *)sender {
    dispatch_async(self.workerQueue, ^{
        if (self.lastTimestamp == 0) {
            self.lastTimestamp = sender.timestamp;
            return;
        }

        CFTimeInterval duration = sender.duration;
        if (duration == 0) {
            return;
        }
        double numberOfFramesDouble = round((sender.timestamp - self.lastTimestamp) / duration);
        NSAssert(numberOfFramesDouble <= NSIntegerMax && numberOfFramesDouble >= NSIntegerMin, @"fps double value out of range of NSInteger");
        NSInteger numberOfFrames = numberOfFramesDouble;
        self.lastTimestamp = sender.timestamp;
        [self calculateFrameDropForNumberOfFrames:numberOfFrames];
    });
}

- (void)calculateFrameDropForNumberOfFrames:(NSInteger)numberOfFrames {
    NSInteger droppedFrameCount = numberOfFrames - 1 > 0 ? numberOfFrames : 0;
    self.currentFrameDropCount += droppedFrameCount;
    if (droppedFrameCount > 0) {
        self.currentFrameDropEventCount += 1;
    }
    if (droppedFrameCount > 0 &&
        self.listener &&
        [self.delegate respondsToSelector:@selector(framesDropped:cumulativeFramesDropped:cumulativeFrameDropEvents:)]) {
        [self.delegate framesDropped:droppedFrameCount
             cumulativeFramesDropped:self.currentFrameDropCount
           cumulativeFrameDropEvents:self.currentFrameDropEventCount];
    }
}

@end

usage.h

/*
The MIT License

Copyright (c) 2010-2018 Google, Inc. http://angularjs.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#ifndef usage_h
#define usage_h

#import <mach/mach.h>

double cpu_usage(int64_t *count);
float mem_usage();

#endif /* usage_h */

usage.m

/*
The MIT License

Copyright (c) 2010-2018 Google, Inc. http://angularjs.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#import <mach/mach.h>
#import "usage.h"

double cpu_usage(int64_t *count)
{
    kern_return_t kr;
    task_info_data_t tinfo;
    mach_msg_type_number_t task_info_count;

    task_info_count = TASK_INFO_MAX;
    kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &task_info_count);
    if (kr != KERN_SUCCESS) {
        return -1;
    }

    task_basic_info_t      basic_info;
    thread_array_t         thread_list;
    mach_msg_type_number_t thread_count;

    thread_info_data_t     thinfo;
    mach_msg_type_number_t thread_info_count;

    thread_basic_info_t basic_info_th;
    uint32_t stat_thread = 0;
    basic_info = (task_basic_info_t)tinfo;

    kr = task_threads(mach_task_self(), &thread_list, &thread_count);
    if (kr != KERN_SUCCESS) {
        return -1;
    }
    if (thread_count > 0)
        stat_thread += thread_count;

    long tot_sec = 0;
    long tot_usec = 0;
    double tot_cpu = 0;
    uint j;

    for (j = 0; j < thread_count; j++)
    {
        thread_info_count = THREAD_INFO_MAX;
        kr = thread_info(thread_list[j], THREAD_BASIC_INFO,
                         (thread_info_t)thinfo, &thread_info_count);
        if (kr != KERN_SUCCESS) {
            return -1;
        }

        basic_info_th = (thread_basic_info_t)thinfo;

        if (!(basic_info_th->flags & TH_FLAGS_IDLE)) {
            tot_sec = tot_sec + basic_info_th->user_time.seconds + basic_info_th->system_time.seconds;
            tot_usec = tot_usec + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds;
            tot_cpu = tot_cpu + basic_info_th->cpu_usage / (double)TH_USAGE_SCALE * 100.0;
        }

    }

    kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));

    if (count) {
        *count = thread_count;
    }
    
    return tot_cpu;
}

float mem_usage()
{
    struct mach_task_basic_info info;
    mach_msg_type_number_t size = MACH_TASK_BASIC_INFO_COUNT;
    kern_return_t kerr = task_info(mach_task_self(), MACH_TASK_BASIC_INFO, (task_info_t)&info, &size);
    return ( kerr == KERN_SUCCESS ) ? info.resident_size : 0;
}

swift translation of KSScrollPerformanceDetector:

import Foundation

public protocol KSScrollPerformanceDetectorDelegate: NSObjectProtocol {
    func framesDropped(count: Int, cumulativeCount: Int, cumulativeEventsCount: Int)
}

public class KSScrollPerformanceDetector: NSObject {

    public private(set) var currentFrameDropCount: Int
    public private(set) var currentFrameDropEventCount: Int
    public weak var delegate: KSScrollPerformanceDetectorDelegate?
    internal var lastTimestamp: CFTimeInterval
    internal var workerQueue: DispatchQueue

    internal lazy var displayLink: CADisplayLink = {
        let link = CADisplayLink(target: self, selector: #selector(displayLinkTriggered(_:)))
        link.isPaused = true
        link.add(to: RunLoop.main, forMode: .common)
        return link
    }()

    public override init() {
        self.lastTimestamp = 0
        self.workerQueue = DispatchQueue(label: "com.frame-rate-reporter.worker", qos: .userInitiated, attributes: .concurrent)
        self.currentFrameDropCount = 0
        self.currentFrameDropEventCount = 0
        super.init()
        self.registerLifecyleNotifications()
    }

    deinit {
        NotificationCenter.default.removeObserver(self)
        self.displayLink.isPaused = true
        self.displayLink.invalidate()
    }

    // Mark: init helpers
    internal func registerLifecyleNotifications() {
        NotificationCenter.default.addObserver(self, selector: #selector(notifyActivate(_:)), name: UIApplication.didBecomeActiveNotification, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(notifyDeactivate(_:)), name: UIApplication.willResignActiveNotification, object: nil)
    }

    // Mark: Public methods
    public func resume() {
        self.displayLink.isPaused = false
    }

    public func pause() {
        self.displayLink.isPaused = true
    }

    public func clearFrameRate() {
        self.workerQueue.async { [weak self] in
            guard let self = self else { return }
            self.currentFrameDropCount = 0
            self.currentFrameDropEventCount = 0
        }
    }

    //Mark: private methods

    @objc internal func displayLinkTriggered(_ sender: CADisplayLink) {
        self.workerQueue.async {
            guard sender.duration != 0 else { return }
            defer { self.lastTimestamp = sender.timestamp }
            guard self.lastTimestamp != 0 else { return }
            let numberOfFramesDouble = round((sender.timestamp - self.lastTimestamp)/sender.duration)
            assert(numberOfFramesDouble <= Double(Int.max) && numberOfFramesDouble >= Double(Int.min))
            let numberOfFrames = Int(numberOfFramesDouble)
            self.calculateFrameDrop(for: numberOfFrames)
        }
    }

    internal func calculateFrameDrop(for numberOfFrames: Int) {
        let droppedFrameCount = numberOfFrames - 1 > 0 ? numberOfFrames : 0 // pretty sure that could just be max(numberOfFrames, 0)
        guard droppedFrameCount > 0 else { return }
        self.currentFrameDropCount += droppedFrameCount
        self.currentFrameDropEventCount += 1
        self.delegate?.framesDropped(count: droppedFrameCount, cumulativeCount: self.currentFrameDropCount, cumulativeEventsCount: self.currentFrameDropEventCount)
    }

    @objc internal func notifyActivate(_ notification: NSNotification) {
        self.resume()
        self.lastTimestamp = 0
    }

    @objc internal func notifyDeactivate(_ notification: NSNotification) {
        self.pause()
    }
}