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

 

Afghanistan: 'We have won the war, America has lost', say Taliban (14 Apr 2021)

 

George Floyd death: Ex-officer Chauvin will not take the stand (15 Apr 2021)

 

US imposes sanctions on Russia over cyber-attacks (15 Apr 2021)

 

France urges citizens to leave Pakistan amid anti-French protests (15 Apr 2021)

 

Why are so many babies dying of Covid-19 in Brazil? (14 Apr 2021)

 

Torres Strait 8: Australian Islanders in landmark climate fight (14 Apr 2021)

 

Why Australia is in hysterics over a 'navy twerking' dance (15 Apr 2021)

 

William Amos: Canadian politician seen naked in work Zoom call (15 Apr 2021)

 

China 'can save .6 trillion by scrapping coal', report says (15 Apr 2021)

 

Texas students disciplined over 'slave trade game' (15 Apr 2021)

more »

 

SF Gate

 

It pays to search for top-quality auto shop (6 Feb 2021)

 

Fired Boeing CEO is now working with Bay Area tractor startup (14 Dec 2020)

 

PG&E bills to rise over per year on average to fund wildfire risk reduction (5 Dec 2020)

 

Nasdaq seeks more diversity on boards of companies listed on exchange (2 Dec 2020)

 

Elizabeth Holmes Prosecutors Say Texts Show Theranos Beset With Problems (24 Nov 2020)

 

Ship traffic, November 1 (30 Oct 2020)

more »


Site feed Updated: 2021-Apr-13 15:00