timing

问题 I've started experimenting with Gameboy programming using Z80 assembly, but I've found something kind of weird. I found a snippet of code used to create a delay: simpleDelay: dec bc ld a,b or c jr nz, simpleDelay ret While playing around with that, I discovered that writing dec bc twice shortens the delay, but writing it 3 times makes the delay longer than using it once or twice. Why does having an even number of dec statements shorten the delay? EDIT: Here's the snippet of code calling the

问题 When you use the postDelayed function on a handler, a delayMillis variable is required to specify the time after which the handler runs. I want my handler to repeat indefinitely so I have nested two postDelayed functions. final int initialdt = 1000; final Handler handler = new Handler(); final Runnable r = new Runnable() { public void run() { handler.postDelayed(this, initialdt); } }; handler.postDelayed(r, initialdt); However using this method, the time between the run() calls is fixed.

问题 In this line, which RDD is being persisted? dropResultsN or dataSetN? dropResultsN = dataSetN.map(s -> standin.call(s)).persist(StorageLevel.MEMORY_ONLY()); Question arises as a side issue from Apache Spark timing forEach operation on JavaRDD, where I am still looking for a good answer to the core question of how best to time RDD creation. 回答1: dropResultsN is the persisted RDD (which is the RDD produced by mapping dataSetN onto the method standin.call() ). 回答2: I found a good example of this

问题 Normally the execution of a setTimeout() method is aborted by a clearTimeout() method that is outside of the setTimeout() method, but in my situation I need to abort the execution of a setTimeout() loop within the loop itself if a certain event occurs during the designated "waiting period". In my code shown below, the user gets 500 milliseconds to activate Code A. If he fails to activate Code A within the time frame, Code B will be executed as a fallback. Within Code A I have marked two

问题 I'm trying to profile a function in another method, so in order to measure its time, I'm doing something like this: double diffTime = GetCurrentTime() - m_lastTime; SuspendOtherProcessThreads(); double runningTime += diffTime; ... Do profiling stuff ... ResumeOtherProcessThreads(); m_lastTime = GetCurrentTime(); ... Let profiled process run .... This is what I do each sample and I consider the time in which I sampled to be "runningTime". But for some reason I get that "runningTime" is much

问题 I have an application where I have some other signal referenced to the system clock ( time.time() ) and I would like to record the audio input and figure out when it happened relative to the other signal. At first I tried using the callback API, thinking that they would occur right when the data was available from the sound card. You would expect the callbacks to occur regularly with a difference of roughly the sample period * number of samples, but as other have noted, this isn't the case. I

问题 I am making a game program in turbo c++ for my project and I need help on how to add a game timer, I've seen videos on how to create timer using while loop but I don't know how to implement it to my game. My plan for my game is to have it show 6 initialized letters(ex. "N A E B T S") and within 30 secs input as many words as possible which has corresponding points(6=10pts, 5=8pts, 4=6pts, 3=4pts). The correct words are written in a txt file with their corresponding points. Also the whole

问题 I was trying out an experiment with Python, trying to find out how many times it could add one to an integer in one minute's time. Assuming two computers are the same except for the speed of the CPUs, this should give an estimate of how fast some CPU operations may take for the computer in question. The code below is an example of a test designed to fulfill the requirements given above. This version is about 20% faster than the first attempt and 150% faster than the third attempt. Can anyone

问题 The system I'm working on needs to consume an IEnumerable of work items, iterate through each of them, and in between them wait for a certain period of time. I would like to keep the system as simple as possible at the enumeration site. That is, I'd like to have a method that I can call at the end of the foreach block which will block for the specific amount of time I specify - but I don't want to use Thread.Sleep because it's impossible to guarantee precision. The minimum amount of time I'll

问题 I'm writing a kernel module that requires function called in 0.1ms intervals measured with at least 0.01ms precision. 250MHz ARM CPU, the HZ variable (jiffies per second) is 100 so anything jiffies-based is a no-go unless I can increase jiffies granularity. Any suggestions where/how to look? 回答1: Assuming the kernel you are running has the Hi-Res timer support turned on (it is a build time config option) and that you have a proper timer hardware which can provide the needed support to raise