tungwaiyip.info

home

about me

links

Blog

< July 2009 >
SuMoTuWeThFrSa
    1 2 3 4
5 6 7 8 91011
12131415161718
19202122232425
262728293031 

past articles »

Click for San Francisco, California Forecast

San Francisco, USA

 

Exploring parallel programming

When I first started blogging, I have a lot of geeky posting about software development. The idea of blogging is to write on short subjects frequently. It is different from writing a long article, which is so burdensome many people end up not doing it at all. But in practice, I have not lived up to expectation of a prolific blogger. Sometimes the gap between postings can be a few months.

Anyway this is the quick posting on geeky subject that I think I should do more. Recently I am working on high performance computing and number crunching task. I have dipped into writing C extension for Python for performance. I got spectacular result from the exercise. It is the best of both world. Programming in Python supplement by C is still very agile and iterative. On the other hand C is giving the performance unachievable with pure Python.

I am started to look into the multiprocessing module introduced in Python 2.6. It is a library to run multiple python processes. With an interface similar to the threading module, it is positioning itself as an alternative approach to threading to circumvent the limitation of Python's GIL. I haven't give much thought to it initially. But looking closer, I find it is really more than just an alternative to threading. It is really a parallel programming framework. For example, the method Pool.map() is really a prototype of a mapreduce framework. I am quite excited to explore this module in the coming days.

Another module I am looking at is the ctypes module. It allows Python code to call C functions directly. Again I haven't thought much about it when it was introduced in Python 2.5. That's because I haven't have a use case of it. Now that I am writing C module, I begin to realize how revolutionary it is. C module delivery great performance. But writing one is a pain. Just the need to keep track of reference count may double the number of lines of your code. For me I am not building a reusable module for other people. It is one off function for me to do number crunching. Using ctypes may allow me easier access to C without the burden of actually writing a Python module.

2009.07.12 [, ] - comments

 

 

blog comments powered by Disqus

past articles »

 

BBC News

 

Coronavirus: Worst economic crisis since 1930s depression, IMF says (09 Apr 2020)

 

EU agrees €500bn coronavirus rescue package (09 Apr 2020)

 

Oil producers agree to cut production by a fifth (09 Apr 2020)

 

Coronavirus: Is it too soon for a movie about it? (09 Apr 2020)

 

Clothing makers in Asia give stark coronavirus warning (10 Apr 2020)

 

Mysteries of decorated ostrich eggs in British Museum revealed (09 Apr 2020)

 

Coronavirus: Spain PM sees 'fire coming under control' (09 Apr 2020)

 

UK PM out of intensive care but still in hospital (09 Apr 2020)

 

Coronavirus: WHO chief and Taiwan in row over 'racist' comments (09 Apr 2020)

 

Coronavirus: Bangladesh locks down a million in Rohingya camps (09 Apr 2020)

more »

 

SF Gate

 

Ship traffic, April 10 (9 Apr 2020)

 

Hackers take to Zoombombing during pandemic (9 Apr 2020)

 

Ship traffic, April 9 (8 Apr 2020)

 

Ship traffic, April 8 (7 Apr 2020)

 

Ship traffic, April 7 (6 Apr 2020)

 

GM, Honda will team up on 2 electric vehicles (5 Apr 2020)

more »


Site feed Updated: 2020-Apr-09 18:00