Home » Latest Technology » What’s New? Intel Threading Building Blocks 4.2

What’s New? Intel Threading Building Blocks 4.2


One of the vital absolute best identified C++ threading libraries Intel Threading Constructing Blocks (Intel TBB) used to be not too long ago up to date to a brand new free up four.2. The up to date model incorporates a number of key new options evaluating to earlier unlock four.1. A few of them have been already launched in Intel TBB four.1 updates.

The brand new synchronization primitive speculative_spin_mutex introduces give a boost to for speculative locking. This has transform conceivable the usage of the Intel® Transactional Synchronization Extensions (Intel® TSX) hardware function to be had in 4th era Intel® Core™ processors. On processors that toughen hardware transactional reminiscence (like Intel® TSX), speculative mutexes work by means of letting a couple of threads accumulate the identical lock, so long as there are not any “conflicts” that can generate totally different outcomes than non-speculative locking. So no serialization occurs in non-contended circumstances. This will likely considerably give a boost to efficiency and scalability for “brief” crucial sections. If there’s no hardware make stronger for transactional synchronization, speculative mutexes behave like their non-speculating counterparts, however presumably with worse efficiency.

Intel TBB now helps the precise exception propagation characteristic (in keeping with C++eleven exception_ptr). With exception_ptr, exception objects will also be safely copied between threads. This brings flexibility in exception managing in a multithreaded surroundings. Now precise exception propagation is on hand in prebuilt binaries for all systems: OS X*, Home windows* and Linux*. On OS X there are two units of binaries: the primary is linked with the gcc usual library – it’s utilized by default and doesn’t enhance actual exception propagation. To make use of the function, you will have to take the 2d set of binaries linked with libc++, the C++ same old library in Clang. To make use of these, arrange the Intel TBB atmosphere and construct your utility within the following approach:

     # tbbvars.sh libc++
     # clang++ -stdlib=libc++ -std=c++eleven concurrent_code.cpp -ltbb

Along with concurrent_unordered_set and concurrent_unordered_map containers, we now present concurrent_unordered_multiset and concurrent_unordered_multimap in response to Microsoft* PPL prototype. concurrent_unordered_multiset offers the flexibility to insert an merchandise greater than as soon as, which isn’t imaginable in concurrent_unordered_set. In a similar fashion, concurrent_unordered_multimap lets in inserting multiple <key,price> pair with the identical key price. For each “multi” containers to find will return the primary merchandise (or <key,price> pair ) within the desk with an identical search key.

Intel TBB containers can now be quite simply initialized with price lists as designated with the aid of C++ eleven (initializer lists):

1 tbb::concurrent_vector<int> v (1,2,three,four,5 );

At present initialize lists are supported by way of the next containers:


The scalable reminiscence allocator has caches for allotted reminiscence in every thread. That is achieved for the sake of efficiency, however steadily at the price of elevated reminiscence utilization. Even supposing the reminiscence allocator tries laborious to steer clear of extreme reminiscence utilization, for complicated circumstances Intel TBB four.2 offers extra regulate to the programmer: it’s now imaginable to scale back reminiscence consumption by way of cleansing thread caches with the scalable_allocation_command() perform. There have been additionally a few enhancements in total allocator efficiency.

Intel TBB library is extensively used on completely different structures. Cell builders can now in finding prebuilt binary information for Android within the Linux OS bundle. Binary information for Home windows Retailer functions have been delivered to the Home windows OS bundle.

Atomic variables tbb::atomic<T> now have constructors when utilized in C++eleven. This permits programmers to price-initialize them on assertion, with const expressions correctly supported. Presently this works for gcc and Clang compilers:

The brand new group preview characteristic permits ready unless all employee threads terminate. This can be wanted if an software forks approaches, or if the Intel TBB dynamic library can also be unloaded at runtime (e.g. if Intel TBB is part of a plugin). To let ready for employees, initialize the task_scheduler_init object this fashion:

2 tbb::task_scheduler_init scheduler_obj (threads, zero, /*wait_workers=*/authentic);

To find the brand new Intel TBB four.2 at commercial and open source web sites. Obtain and revel in the brand new performance!