我正在尝试测量使用 AFNetworking 下载文件时每个 GET 请求所花费的时间。我在循环中重复下载文件。 我遇到的问题是，我测量总时间的方式给出的总时间比实际时间长得多。例如，对于 50 次下载，它给出了 72 秒，但实际上只用了大约 5 秒。我还怀疑 5 秒对于 50 次下载来说太短了(每个文件的下载大小为 581 kb)。
在这种情况下，我如何有效地测量时间？从发出请求到收到响应，我需要时间。
我下载文件的方法:
- (void) HTTPGetRequest
{
startTime = CACurrentMediaTime(); // Start measuring time
AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:http://myServer];
NSMutableURLRequest *request = [httpClient requestWithMethod:@"GET"
path:@"/download/Text581KB.txt"
parameters:nil];
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
[httpClient registerHTTPOperationClass:[AFHTTPRequestOperation class]];
// Save downloaded file
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:[NSString stringWithFormat:@"Text581KB.txt"]];
operation.outputStream = [NSOutputStream outputStreamToFileAtPath:path append:NO];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
double elapsedTime = (CACurrentMediaTime() - startTime); // Measuring time
totalTime += elapsedTime; // Measuring total time HERE!
[results setString:[NSString stringWithFormat: @"Current Transaction Time: %f sec\nTotal Time: %f sec", elapsedTime, totalTime]];
[_resultLabel performSelectorOnMainThread:@selector(setText:) withObject:results waitUntilDone:NO];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(@"Error: %@", error);
}];
[operation setDownloadProgressBlock:^(NSUInteger bytesWritten, long long totalBytesWritten, long long totalBytesExpectedToWrite) { ((int)totalBytesExpectedToWrite));
totalDownloadSize += totalBytesExpectedToWrite;
[_DataTransferredLabel setText:[NSString stringWithFormat:@"Total Download Size: %@", [self getFileSize:totalDownloadSize/1024]]];
}];
[operation setCacheResponseBlock:^NSCachedURLResponse *(NSURLConnection *connection, NSCachedURLResponse *cachedResponse) {
return nil;
}];
[operationQueue addOperation:operation];
}
我正在我的 viewDidLoad 中创建一个 NSOperationQueue:
operationQueue = [NSOperationQueue new];
[operationQueue setMaxConcurrentOperationCount:1]; // using this as I was suspecting downloads were happening in parallel & thus 50 downloads finishing in a few secs
我正在调用 HTTPGetRequest 方法，如下所示:
- (IBAction)startDownload:(UIButton *)sender {
totalCount = [[_countText text] longLongValue]; // get # of times to download
long currentCount = 1;
completedCount = 0;
totalTime = 0;
totalDownloadSize = 0;
while (currentCount <= totalCount)
{
[self HTTPGetRequest];
[results setString:@""];
currentCount++;
}
最佳答案
关于ios - 在 AFNetworking HTTP GET 中测量响应时间，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/16498244/