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Produits similaires:
 la suite

Produits similaires:

• Linux System Programming
• la suite

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Note: - Walk before you run
With all the sophisticated tools available today such as OpenMP, this book may seem quaint. However before grasping at concepts or just using tools with out any understanding or their make up it would be wise to add this to your learning curve.

This book gives a good basic understanding of Pthreads. Of course you will later have to apply it to the real world but as a learning tool this is pretty darn good. The website or path on the sight has changed since publication; but the examples are still there. Because I am using AIX it does take a little time to convert from a gcc format to an AIX format. Then a little more time to apply AIX specific advantages.

As you go from the front of the book to the end the samples get added to and new concepts become available. There are plenty of diagrams for the visual learner. I personally found the signal handling of great use.

Any way this book is not the end-all, be-all, of threads but it sure cleared a lot of concepts up for me.

1. Why Pthreads
2. Designing threaded programs
3. Synchronizing Pthreads
4. Managing Pthreads
5. Pthreads and UNIX
6. practical Considerations

Using OpenMP: Portable Shared Memory Parallel Programming (Scientific and Engineering Computation)

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Note: - Good for learning the basics but incomplete for modern multithreading programming
This book does a nice job for describing the pthread API. When I have read this book, my multithread programming experience was mainly with Win32 threads and reading this book was my first exposure to the condition synchronization objects. With the help of this book, it has been a breeze to learn how to use conditions. What is missing from this book written 10 years ago, which is also missing in all multithread books that I have read of that era, is coverage on issues with parallel processing. If all you have to do with threads is to launch a background job while keeping UI responsive or asynchronous I/O on a single core processor, you will be fine with this book.

However, if you try to crunch an array of data with multiple threads each processing their own chunk of the array, you could fall into cache line alignment problems even if your threads does not access the same memory locations. Those problems are platform dependant. I have written such a program that was working wonderfully well with a Sparc station and a PowerPC based station but once ported to a x86 architecture, the program was actually becoming slower than the single thread version. It is very hard to get it right. You have to be careful about the array alignment in memory and where the boundaries of the chunks of data that you assign to threads are. What will happen if 2 threads located on 2 different processors access to the same cache line is that one processor will have to flush that cache line back to the main memory and the other processor will have to fetch the values back from the main memory to its cache. The overhead of this is so huge that processing the array from a single thread could be faster.

I still have to find a book that addresses these problems. I expect it to come soon with dual and quad core processors becoming mainstream but this is not this book.

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Note: - * o'reilly should be embarrased!! ...
I read the book a number of years ago to learn pthreads.
I found numerous errors in the examples -- speaking
at work to a colleague I recall we laughed at this book --
It was such a disaster.

I may read the book again (over the last few years I learned a lot about
pthreads) and give a careful analysis of it.

I had a first printing -- there were gobs of errata on
Oreilly's site -- maybe they put in enough corrections so
the examples run -- but I'm amazed how shoddy the first printing was.

Stay away from it...

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Note: - Pretty Good
I found it too be an excellent overview. Its treatment of the issues associated with threads and signals I think was especially useful. My only complaint is with the Quick Reference in Appendix C. The reference provides no description of possible function call errors. While I admit the errors are dependant on the particular Pthreads implementation, however there are a core number of errors that would be common throughout all, or at least most, implementations. The point is if you are to do any actual programming, which I presume is the reason for a reference of function calls, you need to know what return values to expect. Providing no reference would have been better then providing a useless one.

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Note: - * Not the best effort I've read... ...
The short code snippets are horrible. If the author wants to save money and space by using code snippets, it should be checked and checked again for accuracy. There are numerous errors in the code. For example, on page 80, there is an example of condition variable usage. However, there are no function prototypes! This is just one of numerous obvious ommissions. Trust me, there are non-obvious errors too. If you're looking for an overview, this will do you fine. However, if you're looking for some decent code examples to look at, I'd suggest Butenhof's book instead.

Multi-threaded programming is difficult enough, why make it harder for yourself?