#100DaysOfCode in Python Transcripts
Chapter: Days 49-51: Measuring performance
Lecture: Demo: Focus on our code
0:00 Now one takeaway from this here
0:02 is that we're actually spending a ton
0:04 of startup time and other things.
0:06 And depending on how your code is working,
0:09 if it's intended to be called over and over again,
0:12 this is very common if you use like a web app,
0:14 and you start it and every time somebody hits this page,
0:16 some stuff is going to happen over and over.
0:19 You might not want to measure
0:20 the start up time so much as steady state time.
0:24 So let's do one real quick thing
0:25 before we actually get fully to the CPython API.
0:29 Let's just run this a lot.
0:31 So, then here we have this main.
0:33 Let's just run main like 100 times, or 50 times,
0:36 or something like that.
0:37 And measure that.
0:39 That will get rid of some of the variation.
0:40 It'll definitely suppress
0:42 some of the module Python startup times.
0:44 So we'll just say this.
0:47 Let's do it 25 times.
0:50 Now we're here and we'll run the same thing.
0:53 Once again, but it'll take a little bit longer.
0:55 Still, not long, right?
0:58 But you can see, it's going over and over again
1:00 it's doing this little printout here.
1:02 So now if we look over here,
1:03 here's our main, spending a little bit of time there.
1:07 Doing our research initialization,
1:09 we're spending a decent amount of time in parse row.
1:13 Over here, these are cumulative times.
1:15 So, like, for example, we're spending 210 milliseconds in module load,
1:18 but now we're spending 180 milliseconds in main.
1:23 That may be totally fast enough, maybe not.
1:25 On the Talk Python Training website,
1:28 we try to get things down to 10 milliseconds, 20 milliseconds.
1:33 Some of the pages that are really complicated,
1:34 you know, there's a lot going on.
1:36 It's like 50 milliseconds.
1:37 But you certainly want to try to get that number down.
1:39 I think if this was a web app,
1:41 that number would be too high.
1:43 Of course it's not, but what we're going to do is
1:45 we're going to look at what we're doing here
1:47 and at first try to understand why this is happening
1:50 and how we can make it faster.