python performance profiling

packaging performance: The amount of data packaged is 1116 bytes (8+1108) #! /usr/bin/env python #coding =utf-8 import time import struct Test_data = {' Baihe ': {' name ': Unicode (' Lily ', ' Utf-8 '), ' say ': Unicode (' Fresh, elegant, floral ', ' utf-8 '), ' grow_time ': 0.5, ' fruit_time ': 0.5, ' Super_time ': 0.5, ' total_time ': 1, ' buy ': {' Gold ': 2,}, ' Harvest_fruit ': 1, '

;>> print c.areaComputing area12.5663706144>>> print c.area12.5663706144 "Computing area" is printed every time calculated in area (). after calling c. area twice in a row, "Computing area" is printed only once. This benefits from LazyProperty. after a call, no matter how many subsequent calls are called, the calculation will not be repeated. --> The above is a detailed description of the delay initialization method for improving Python

1. Confusion Matrixis a confusion matrix of two types of problems in which the output uses a different category labelCommonly used metrics to measure classification performance are: The correct rate (Precision), which is equal to tp/(TP+FP), gives the ratio of the true positive example in the sample that is predicted to be a positive example. recall Rate (Recall), which he equals to tp/(TP+FN), gives the true positive example of the predi

Always want to do the development of language performance comparison, just have time to do a reference to everyone,Compiled classes: C + + and Java are doing fineScript class: TCC scripts run C language dynamically, performance is much faster than other scripts ...Want to play TCC classmate Download test package, TCC Directory modified script.c, run TccTest1.exe can see the effect of modification, no need t

Performance comparison (transfer from http://www.linuxidc.com/Linux/2012-07/66404.htm)I knew it was more efficient to use set in Python, but I didn't think there was such a big gap:~$ python-m Timeit-n "[x for X in range (+) if x in range (500, 1500)]"Loops, Best of 3:28.2 msec per loop~$ python-m Timeit-n "set (range)

computer implementation will also have a certain difference. However, the relative difference between each method should be considerable. As you can see from the results,beautiful Soup is more than 7 times times slower than the other two methods when crawling our sample Web pages. In fact, this result is expected because lxml and regular expression modules are written in C , while beautiful Soup is written in pure Python . An interesting fact is that

Recently made a simple demo request, build an HTTP server, support simple QA query. There are 10,000 QA pairs in the library that need to support more than 10,000 requests per second.The demand is relatively simple, the main difficulty is 10000+ RPS. First, using Python + Uwsgi to write a simple demo, after the test found that RPS only thousands of, not up to performance requirements. Later, multiple servic

Python data type: Dual-ended queueWhen it comes to container types, the first thing you think about is the list, and the list really solves most of the need, but when it comes to a fairly large amount of data in the list, the performance issue is especially important, and when the list is maliciously injected with an infinite amount of data, it can expose a security issue. A better alternative is: Collectio

Http://www.aikaiyuan.com/5318.htmlThe most common tool for Web services to do performance load testing is the Apache benchmark commonly known as AB and Commercial tool LoadRunner. AB Simple direct, the function is also relatively weak, but we often see some of the Web server or the framework of performance testing with AB, and the LoadRunner function is indeed very powerful, a variety of large software com

#!/bin/env python#coding: UTF8‘‘‘awk prints the specified number of rowsSED prints the specified number of linesPython prints the specified position, a length stringAwk takes the longest, a long timeSed awk time HalfPython time-consuming basic negligibleWhen you use a script to monitor log files, the location of the last exit is loggedPython is the most efficient.‘‘‘Import OSFrom time Import timeFrom Os.path import GetSizetestfile= '/dev/shm/%s '% tim

# print result. read () self. deal_data (result. read (). decode ('gbk') self. calculate_date (); # extract the content from the page code def deal_data (self, myPage): myItems = re. findall ('.*? (.*?) .*? (.*?) .*?', MyPage, re. s) # obtain credits for item in myItems: self. weights. append (item [0]. encode ('gbk') self. points. append (item [1]. encode ('gbk') # calculate the score. if the score is not displayed or the score is excellent, def calculate_date (self) is not ca

A simple Python script that monitors Redis performance has already talked about how to monitor memcached, and now incidentally how to monitor Redis. Let's start with the following information about monitoring redis: Redis Ping: Verify Ping Redis Alive: Check to see if the port is alive Redis connections: View the number of connections Redis blockedclients: Waiting on the number of block

we calculate only once? This is lazy property.Code implementation class LazyProperty(object): def init(self, func): self.func = func def get(self, instance, owner): if instance is None: return self else: value = self.func(instance) setattr(instance, self.func.name, value) return valueimport mathclass Circle(object): def init(self, radius): self.radius = radius @LazyProperty def area(self): print 'Computing area' return math.pi * self.radius ** 2 @Lazy

some of the scenarios for Python performance improvements. One, function call optimization (space span, avoid access to memory) The core point of optimization of the program is to minimize the operation span, including the span of code execution time and the space span in memory. 1. Big Data summation, using sum A = range (100000)%timeit-n sum (a) loops, best of 3:3.15 ms per Loop%%timeit ...: s = 0 ...

This article describes how to test disk performance using Python. it involves Python's hardware-related operating skills and has some reference value, for more information about how to test disk performance using Python, see the following example. Share it with you for your reference. The details are as follows: The c