背景，目前正在优化项目，首先要对项目内的性能指标进行分析，这个可以通过Instrument 进行debug 分析。这样做只适用于开发人员。性能指标作为一项衡量App的重要指标无法量化。为了每次发布前能有一个性能报告，需要开发一个组件，对性能数据进行记录，之后通过脚本生成报表。
报表中重点关注的指标有以下几点：
启动时间内存FPS（页面刷新帧率）CPU 页面渲染时间
debug模式
主线程阻塞时，输出MainThread 栈信息。
分别介绍如何实现这些数据的采集。
内存
vm_size_t usedMemory(void) {
struct task_basic_info info;
mach_msg_type_number_t size =
sizeof(info);
kern_return_t kerr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&info, &size);
return (kerr == KERN_SUCCESS) ? info.resident_size :
0;
}
FPS
使用CADisplayLink 进行获取
_displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(envokeDisplayLink:)];
[_displayLink addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
- (void)envokeDisplayLink:(CADisplayLink *)displayLink
{
if (_lastTime == 0) {
_lastTime = displayLink.timestamp;
return;
}
_count ++;
NSTimeInterval interval = displayLink.timestamp - _lastTime;
if (interval
< 1 xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed xss=removed> 0)
stat_thread += thread_count;
long tot_sec = 0;
long tot_usec = 0;
float tot_cpu = 0;
int j;
for (j = 0; j
< thread xss=removed xss=removed xss=removed xss=removed>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 / (float)TH_USAGE_SCALE * 100.0;
}
} // for each thread
kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
assert(kr == KERN_SUCCESS);
return tot_cpu;
}
启动时间
+ (
void)load
{
loadTime = mach_absolute_time();
mach_timebase_info(&timebaseInfo);
@autoreleasepool {
__block
id obs;
obs = [[
NSNotificationCenter defaultCenter] addObserverForName:UIApplicationDidFinishLaunchingNotification
object:
nil queue:
nil
usingBlock:^(
NSNotification *note) {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
0), ^{
applicationRespondedTime = mach_absolute_time();
DDLogInfo(
@"VivaVedio_IOS_Start_Time: %.f", MachTimeToSeconds(applicationRespondedTime - loadTime));
});
[[
NSNotificationCenter defaultCenter] removeObserver:obs];
}];
}
}
页面渲染耗时
利用runtime， 将UIViewController 的viewWillAppear， viewDidAppear 进行hook。输出调用的时间间隔。
@interface UIViewController()
@property (
nonatomic,
assign) CFTimeInterval viewControllerAppearDuration;
@end
@implementation UIViewController (Performance)
+ (
void)load{
[
self walle_swizzlingViewWillAppear];
[
self walle_swizzlingViewDidAppear];
}
+ (
void)walle_swizzlingViewWillAppear
{
SEL originalSelector =
@selector(viewWillAppear:);
SEL swizzledSelector =
@selector(walle_viewWillAppear:);
[
self swizzlingInClass:[
self class] originalSelector:originalSelector swizzledSelector:swizzledSelector];
}
+ (
void)walle_swizzlingViewDidAppear
{
SEL originalSelector =
@selector(viewDidAppear:);
SEL swizzledSelector =
@selector(walle_viewDidAppear:);
[
self swizzlingInClass:[
self class] originalSelector:originalSelector swizzledSelector:swizzledSelector];
}
- (
void)walle_viewWillAppear:(
BOOL)animated
{
self.viewControllerAppearDuration = CACurrentMediaTime();
[
self walle_viewWillAppear:animated];
}
- (
void)walle_viewDidAppear:(
BOOL)animated
{
[
self walle_viewDidAppear:animated];
self.viewControllerAppearDuration = CACurrentMediaTime() -
self.viewControllerAppearDuration;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
0), ^{
NSString *name = NSStringFromClass(
self.class);
DDLogInfo(
@"View Controller :%@ show time : %g s", name,
self.viewControllerAppearDuration);
});
}
+ (
void)swizzlingInClass:(Class)cls originalSelector:(SEL)originalSelector swizzledSelector:(SEL)swizzledSelector
{
Class clz = cls;
Method originalMethod = class_getInstanceMethod(clz, originalSelector);
Method swizzledMethod = class_getInstanceMethod(clz, swizzledSelector);
BOOL didAddMethod = class_addMethod(clz, originalSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod));
if (didAddMethod) {
class_replaceMethod(clz, swizzledSelector, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod));
}
else{
method_exchangeImplementations(originalMethod, swizzledMethod);
}
}
- (
void)setViewControllerAppearDuration:(CFTimeInterval)viewControllerAppearDuration
{
objc_setAssociatedObject(
self,
@selector(viewControllerAppearDuration), @(viewControllerAppearDuration), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (CFTimeInterval )viewControllerAppearDuration
{
return [objc_getAssociatedObject(
self,
@selector(viewControllerAppearDuration)) doubleValue];
}
debug 主线程阻塞
通过监控Runloop的回调进行监控
_observer = CFRunLoopObserverCreateWithHandler(kCFAllocatorDefault, kCFRunLoopAllActivities,
true,
0, ^(CFRunLoopObserverRef observer, CFRunLoopActivity activity) {
self->_activity = activity;
dispatch_semaphore_t semaphore =
self->_semaphore;
dispatch_semaphore_signal(semaphore);
});
CFRunLoopAddObserver(CFRunLoopGetMain(), _observer, kCFRunLoopCommonModes);
_semaphore = dispatch_semaphore_create(
0);
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
0), ^{
while (
YES)
{
long st = dispatch_semaphore_wait(_semaphore, dispatch_time(DISPATCH_TIME_NOW,
50*NSEC_PER_MSEC));
if (st !=
0)
{
if (_activity == kCFRunLoopBeforeSources || _activity == kCFRunLoopAfterWaiting)
{
if (++_countTime <
5)
continue;
NSString *track = [BSBacktraceLogger bs_backtraceOfMainThread];
NSLog(
@"############### Main thread is blocked ###############");
NSLog(
@"%@", track);
NSLog(
@"############### Main thread is blocked ###############");
}
}
_countTime =
0;
}
});
