I'm looking for resources that can improve the execution of my code dramatically. The 20% tricks that will get my code to perform faster 80% faster.
Ask HN: What are the 20% tips that will get my code to performance 80% faster?
1–10 of 69 posts
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#2Use a profiler.
Make your code do less work.
Use less memory so more of your code/data fits in the CPU cache.
Understand the algorithms that you use, their strengths and weaknesses.
No magic tricks, just hard work.
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#3Cache.
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#4Use hash tables, hash maps, dictionaries, JavaScript objects, etc. (whatever it's called in your language of choice) for indexing.
This gives you constant time access to data by whatever properties you want to index on (usually by id).
Also, use libraries and reuse your own code/routines. If you find a faster way to do something, all the code that used those routines will benefit immediately.
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#5Use the correct algorithms. O(log n) beats O(n) beats O(n log n) beats O(n^2) almost every time. A common mistake is e.g. using the `in` operator with lists in Python, instead of converting the list to a set first.
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#6I suggest you to read a book about algorithms. This one is pretty good: "Introduction to Algorithms" by Cormen and Rivest.
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#7Reduce round trips.
That might be round trips to a database, round trips to a caching layer, or round trips from client to server.
Generally speaking, grab as much data as you'll need (but not more).
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#8#pragma omp parallel
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#9[deleted]
Re: Ask HN: What are the 20% tips that will get my code to performance 80% faster?
#10I suggest you to read a book about algorithms. This one is pretty good: "Introduction to Algorithms" by Cormen and Rivest.
There is also a lot of great material on Coursera, MIT OpenCourseWare, etc. on algorithms.