Any experiences with Intel's Threading Building Blocks?

Question

Intel's Threading Building Blocks (TBB) open source library looks really interesting. Even though there's even an O'Reilly Book about the subject I don't hear about a lot of people using it. I'm interested in using it for some multi-level parallel applications (MPI + threads) in Unix (Mac, Linux, etc.) environments. For what it's worth, I'm interested in high performance computing / numerical methods kinds of applications.

Does anyone have experiences with TBB? Does it work well? Is it fairly portable (including GCC and other compilers)? Does the paradigm work well for programs you've written? Are there other libraries I should look into?

Answer 1

I've looked into TBB but never used it in a project. I saw no advantages (for my purposes) over ZThread. A brief and somewhat dated overview can be found here.

It's fairly complete with several thread dispatch options, all the usual synchronization classes and a very handy exception based thread "interrupt" mechanism . It's easily extendable, well written and documented. I've used it on 20+ projects.
It also plays nice with any *NIX that supports POSIX threads as well as Windows.

Worth a look.

Answer 2

ZThread is LGPL, you are limited to use the library in dynamic linkage if not working in a open source project.

The Threading Building Blocks (TBB) in the open source version, (there is a new commercial version, $299 , don't know the differences yet) is GNU General Public License version 2 with a so-called “Runtime Exception” (that is specific to the use only on creating free software.) I've seen other Runtime Exceptions that attempt to approach LGPL but enabling commercial use and static linking this is not is now the case.

I'm only writing this because I took the chance to examine the libraries licenses and those should be also a consideration for selection based on the use one intends to give them.

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Txs, Jihn for pointing out this update...

Answer 3

Hi Pat,

I have used TBB briefly, and will probably use it more in the future. I liked using it, most importantly because you dont have to deal with macros/extensions of C++, but remain within the language. Also its pretty portable. I have used it on both windows and linux. One thing though: it is difficult to work with threads using TBB, you would have to think in terms of tasks (which is actually a good thing). Intel TBB would not support your use of bare locks (it will make this tedious). But overall, this is my preliminary experience.

I'd also recommend having a look at openMP 3 too.

Answer 4

Have you looked at boost library with its thread API?

Answer 5

I've introduced it into our code base because we needed a bettor malloc to use when we moved to a 16 core machine. With 8 and under it wasn't a significant issue. It has worked well for us. We plan on using the fine grained concurrent containers next. Ideally we can make use of the real meat of the product, but that requires rethinking how we build our code. I really like the ideas in TBB, but it's not easy to retrofit onto a code base.

You can't think of TBB as another threading library. They have a whole new model that really sits on top of threads and abstracts the threads away. You learn to think in task, parallel_for type operations and pipelines. If I were to build a new project I would probably try to model it in this fashion.

We work in Visual Studio and it works just fine. It was originally written for linux/pthreads so it runs just fine over there also.

Answer 6

I'm not doing numerical computing but I work with data mining (think clustering and classification), and our workloads are probably similar: all the data is static and you have it at the beginning of the program. I have briefly investigated Intel's TBB and found them overkill for my needs. After starting with raw pthread-based code, I switched to OPENMP and got the right mix between readability and performance.

Answer 7

The Threading Building Blocks (TBB) in the open source version, (there is a new commercial version, $299, don't know the differences yet) is GNU General Public License version 2 with a so-called “Runtime Exception” (that is specific to the use only on creating free software.) I've seen other Runtime Exceptions that attempt to approach LGPL but enabling comercial use and static linking this is not the case.

According to this question threading building blocks is usable without copy-left restrictions with commercial use.

Answer 8

I use TBB in one project. It seemed to be easier to use it than threads. There are tasks which can be run in parallel. A task is just a call to your parallelized subroutine. Load balancing is done automatically. That is why I accept it as a higher level parallelization library. I achieved 2.5x speed up without much work on a 4 core intel processor. There are examples, they answer questions on forums and it is maintained and it is free.