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转载 Python Patterns - An Optimization Anecdote

Python Patterns - An Optimization AnecdotePython Patterns - An Optimization AnecdoteThe other day, a friend asked me a seemingly simple question: what's the best way to convert a list of integ

2014-08-17 11:26:21 1149

原创 Install Oracle 11g R2 in Centos 6 X64

If the prereuisite CV_ASSUME_DISTID=OEL4 to CV_ASSUME_DISTID=OEL6

2014-07-24 10:41:29 1363

转载 Rich Comparison Methods

One of the nicest features of the Data Model is the ability to override the behavior of rich comparison operators:import functools@functools.total_orderingclass Generic(object): def __ini

2014-07-08 14:03:58 882

转载 Optimizing Linux Memory Management for Low-latency / High-throughput Databases

Table of ContentsIntroductionSetting up the contextReproducing and understanding Linux's zone reclaim behaviorNUMA memory rebalancing also triggers direct page scansLessons learnedIntr

2014-07-07 17:27:30 1332

转载 The ultimate SO_LINGER page, or: why is my tcp not reliable

This post is about an obscure corner of TCP network programming, a corner where almost everybody doesn’t quite get what is going on. I used to think I understood it, but found out last week that I did

2014-06-10 17:22:19 6923

转载 Iterables, Iterators and Generators: Part 2

This is the second part of the talk I gave January 24, 2013 at the Ottawa Python Authors Group.Part One introduces Python iterables and iterators and generators. This part covers the advanced use

2014-06-10 16:13:22 1034

转载 Top 10 Mistakes that Python Programmers Make

About PythonPython is an interpreted, object-oriented, high-level programming language with dynamic semantics. Its high-level built in data structures, combined with dynamic typing and dynamic b

2014-05-24 17:48:01 954

转载 The Light and Dark sides of Python name binding

The Light and Dark sides of Python name bindingPosted on 2014-04-04, last modified 2014-04-09.What does bar.foo do? - An exploration of Python assignment, objects, attributes and descripto

2014-05-20 10:22:15 958

转载 Benchmark of Python WSGI Servers

Benchmark of Python WSGI ServersNicholas Piël | March 15, 2010It has been a while since the Socket Benchmark of Asynchronous server. That benchmark looked specifically at the raw socket perfor

2014-05-01 22:48:33 2832

转载 Asynchronous Servers in Python

Asynchronous Servers in PythonNicholas Piël | December 22, 2009There has already been written a lot on the C10K problem and it is known that the only viable option to handle LOTS of concurre

2014-05-01 22:44:04 1129

转载 A collection of not-so-obvious Python stuff you should know

A collection of not-so-obvious Python stuff you should know!I am really looking forward to your comments and suggestions to improve andextend this little collection! Just send

2014-04-26 23:18:16 1562

原创 openssl CLI

1) Create a self-signed certificate2) Check if a certificate is self-signedopenssl x509 -in cert.pem -inform PEM -nou

2014-04-20 20:05:33 873

转载 OOP Concepts in Python 2.x - Part 2

OOP Concepts in Python 2.x - Part 2Published on: Mar 10th, 2014Tags: pythonPosted by Leonardo GiordaniAbstractThis post continues the analysis of the Python OOP implementatio

2014-04-12 22:41:41 1071

转载 OOP Concepts in Python 2.x - Part 1

OOP Concepts in Python 2.x - Part 1Published on: Mar 5th, 2014Tags: pythonPosted by Leonardo GiordaniAbstractObject-oriented programming (OOP) has been the leading programmin

2014-04-12 17:02:16 1332

转载 Linux I/O Performance Tests using dd

Under Linux, the dd command can be used for simple I/O performance measurements. This article will provide valuable information about which parameters should be used.Contents [hide]

2014-04-08 20:01:10 1162

转载 Default Parameter Values in Python

Default Parameter Values in PythonFredrik Lundh | July 17, 2008 | based on a comp.lang.python post(It happened to me in one of the first Python programs I ever wrote, and it took several yea

2014-03-23 22:53:06 1190

转载 Playing with ptrace, Part I

Using ptrace allows you to set up system call interception and modification at the user level.Have you ever wondered how system calls can be intercepted? Have you ever tried fooling the kern

2014-03-10 20:59:26 900

原创 CherryPy architecture

High Level FrameworkApplication Level Framework

2014-02-22 22:31:35 910

原创 Python debuggers

1) pdb2) Winpdb3) pydev4) gdb python extentionReferences:https://code.google.com/p/winpdb/wiki/DebuggingTutorialhttp://stackoverflow.com/questions/132058/showing-the-stack-trace-from-a-r

2014-02-19 20:00:23 792

原创 volatile in C++

1) "volatile" has nothing to do with multiprocessing. So it is not atomic.2) In a single threaded env, "volatile int vi = 0", vi = 1; int read_back = vi; assert (read_back == 1); the assertion may f

2014-02-13 10:03:13 858

原创 Javascript module/libs

1) jQuery2) RequireJS3) Underscore4) Backbone5)

2014-02-08 22:08:19 795

转载 Metaprogramming in Python

MetaprogrammingMetaprogramming is the ability for a program to reason about itself or to modify.Metaprogramming is the writing of computer programs that write or manipulate other programs (o

2014-01-27 21:41:23 1525

原创 Use unique_ptr to RAII your file objects

auto file_closer = [](int* pfd) { close(*pfd); };int fd = open("a.txt", O_WRONLY|O_CREAT, 0666);unique_ptr raii_fd (&fd, file_closer);// using fd

2014-01-25 16:08:33 730

原创 From LinkedIn

Favorite monitoring / performance tool mostly for Linux Servers on Vmware/Proliant and some Windows servers

2014-01-25 12:11:13 794

原创 Logging

Python logging componentsLoggers expose the interface that application code directly uses.Handlers send the log records (created by loggers) to the appropriate destination.Filters provide a fine

2014-01-19 11:33:00 791

原创 Env setup for MAC OS X

1) Install package management tool "Homebrew" for MAChttp://brew.sh/2) Configure the Terminal's background/foreground and text colors. Default Foreground: 255/255/255Default Backgrou

2014-01-08 18:57:57 1590

转载 Eggs and Egg Info

----------------------Eggs and their Formats----------------------A "Python egg" is a logical structure embodying the release of aspecific version of a Python project, comprising its code,

2014-01-05 16:47:02 2840

转载 Why so many Python web frameworks

Why so many Python web frameworks?When asked about the plethora of web frameworks for Python the answer is often that it is way too easy to put together one in Python. That certainly seems plaus

2014-01-05 11:11:02 1211

转载 The Log: What every software engineer should know about real-time data's unifying abstraction

I joined LinkedIn about six years ago at a particularly interesting time. We were just beginning to run up against the limits of our monolithic, centralized database and needed to start the transition

2013-12-24 16:33:09 1823

转载 Making Your Next Move

This entry is part of a series, RValue References: Moving Forward»Entries in this series:Want Speed? Pass by Value.Making Your Next MoveYour Next Assignment...Exceptionally Moving!On

2013-12-24 15:39:34 884

转载 Want Speed? Pass by Value.

Want Speed? Pass by Value.This entry is part of a series, RValue References: Moving Forward»Entries in this series:Want Speed? Pass by Value.Making Your Next MoveYour Next Assignme

2013-12-24 14:06:18 2134

转载 Kernel Korner - Why and How to Use Netlink Socket

Use this bidirectional, versatile method to pass data between kernel and user space.Due to the complexity of developing and maintaining the kernel, only the most essential and performance-cr

2013-12-24 11:19:17 1087

转载 64-Bit Programming Models: Why LP64?

64-Bit Programming Models: Why LP64?Participation from: Digital Equipment Corporation, Hewlett-Packard Company, IBM Corporation, Intel Corporation, Novell Inc., NCR Corporation (formally AT&T GIS),

2013-12-20 15:22:30 689

转载 64-Bit Programming Models: Why LP64?

64-Bit Programming Models: Why LP64?Participation from: Digital Equipment Corporation, Hewlett-Packard Company, IBM Corporation, Intel Corporation, Novell Inc., NCR Corporation (formally AT&T GIS),

2013-12-20 15:18:15 639

转载 64-Bit Programming Models: Why LP64?

64-Bit Programming Models: Why LP64?Participation from: Digital Equipment Corporation, Hewlett-Packard Company, IBM Corporation, Intel Corporation, Novell Inc., NCR Corporation (formally AT&T GIS),

2013-12-20 15:15:14 797

原创 context manager

1) The "with" statementwith expr [as VAR]: WITH-BLOCK"with" statement is something like "RAII" in C++, when "with" statement finishes, all resources will be cleaned automatically even there i

2013-12-20 12:12:09 1197

原创 Relative imports

For example, code in the A.B.C module can do:from . import D # Imports A.B.Dfrom .. import E # Imports A.Efrom ..F import G # Imports A.F.G

2013-12-20 11:05:54 1159

转载 A guide to analyzing Python performance - Python Performance, 6 of n

A guide to analyzing Python performanceWhile it’s not always the case that every Python program you write will require a rigorous performance analysis, it is reassuring to know that there are a wide v

2013-12-11 21:49:36 1089

转载 Linux下高并发socket最大连接数所受的各种限制

Linux下高并发socket最大连接数所受的各种限制12/06. 20131、修改用户进程可打开文件数限制在Linux平台上，无论编写客户端程序还是服务端程序，在进行高并发TCP连接处理时，最高的并发数量都要受到系统对用户单一进程同时可打开文件数量的限制(这是因为系统为每个TCP连接都要创建一个socket句柄，每个socket句柄同时也是一个文件句柄)。可使用uli

2013-12-11 12:11:43 793

转载 Linux memory manager and your big data

Disclaimer: We always assume that when we have an issue and think it's the operating system, 99% of the time, it turns out to be something else. We therefore caution against assuming that the proble

2013-12-11 11:58:09 872