October 2015
Beginner to intermediate
174 pages
3h 32m
English
Content preview from Python Web Scraping
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Performance
To further understand how increasing the number of threads and processes affects the time required when downloading; here is a spreadsheet of results for crawling 1000 web pages:
|
Script |
Number of threads |
Number of processes |
Time |
Comparison with sequential |
|---|---|---|---|---|
|
Sequential |
1 |
1 |
28m59.966s |
1 |
|
Threaded |
5 |
1 |
7m11.634s |
4.03 |
|
Threaded |
10 |
1 |
3m50.455s |
7.55 |
|
Threaded |
20 |
1 |
2m45.412s |
10.52 |
|
Processes |
5 |
2 |
4m2.624s |
7.17 |
|
Processes |
10 |
2 |
2m1.445s |
14.33 |
|
Processes |
20 |
2 |
1m47.663s |
16.16 |
The last column shows the proportion of time in comparison to the base case of sequential downloading. We can see that the increase in performance is not linearly proportional to the number of threads and processes, but appears logarithmic. For ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.