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Reference documentation for deal.II version 8.5.1
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Reference documentation for deal.II version 8.5.1
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#include <deal.II/lac/vector_memory.h>
Classes | |
| struct | Pool |
Public Types | |
| typedef types::global_dof_index | size_type |
Public Member Functions | |
| GrowingVectorMemory (const size_type initial_size=0, const bool log_statistics=false) | |
| virtual | ~GrowingVectorMemory () |
| virtual VectorType * | alloc () |
| virtual void | free (const VectorType *const) |
| virtual std::size_t | memory_consumption () const |
 Public Member Functions inherited from VectorMemory< VectorType > | |
| virtual | ~VectorMemory () |
| Public Member Functions inherited from Subscriptor | |
| Subscriptor () | |
| Subscriptor (const Subscriptor &) | |
| Subscriptor (Subscriptor &&) | |
| virtual | ~Subscriptor () |
| Subscriptor & | operator= (const Subscriptor &) |
| Subscriptor & | operator= (Subscriptor &&) |
| void | subscribe (const char *identifier=0) const |
| void | unsubscribe (const char *identifier=0) const |
| unsigned int | n_subscriptions () const |
| void | list_subscribers () const |
| template<class Archive > | |
| void | serialize (Archive &ar, const unsigned int version) |
Static Public Member Functions | |
| static void | release_unused_memory () |
| Static Public Member Functions inherited from VectorMemory< VectorType > | |
| static ::ExceptionBase & | ExcNotAllocatedHere () |
| Static Public Member Functions inherited from Subscriptor | |
| static ::ExceptionBase & | ExcInUse (int arg1, char *arg2, std::string &arg3) |
| static ::ExceptionBase & | ExcNoSubscriber (char *arg1, char *arg2) |
Private Types | |
| typedef std::pair< bool, VectorType * > | entry_type |
Private Attributes | |
| size_type | total_alloc |
| size_type | current_alloc |
| bool | log_statistics |
Static Private Attributes | |
| static Pool | pool |
| static Threads::Mutex | mutex |
A pool based memory management class. See the documentation of the base class for a description of its purpose.
Each time a vector is requested from this class, it checks if it has one available and returns its address, or allocates a new one on the heap. If a vector is returned, through the free() member function, it doesn't return it to the operating system memory subsystem, but keeps it around unused for later use if alloc() is called again, or until the object is destroyed. The class therefore avoid the overhead of repeatedly allocating memory on the heap if temporary vectors are required and released frequently; on the other hand, it doesn't release once-allocated memory at the earliest possible time and may therefore lead to an increased overall memory consumption.
All GrowingVectorMemory objects of the same vector type use the same memory Pool. Therefore, functions can create such a VectorMemory object whenever needed without performance penalty. A drawback of this policy might be that vectors once allocated are only released at the end of the program run. Nevertheless, the since they are reused, this should be of no concern. Additionally, the destructor of the Pool warns about memory leaks.
Definition at line 236 of file vector_memory.h.
| typedef types::global_dof_index GrowingVectorMemory< VectorType >::size_type |
Declare type for container size.
Definition at line 242 of file vector_memory.h.
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Type to enter into the array. First component will be a flag telling whether the vector is used, second the vector itself.
Definition at line 292 of file vector_memory.h.
| GrowingVectorMemory< VectorType >::GrowingVectorMemory | ( | const size_type | initial_size = 0, |
| const bool | log_statistics = false |
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Constructor. The argument allows to preallocate a certain number of vectors. The default is not to do this.
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Destructor. Release all vectors. This destructor also offers some statistic on the number of allocated vectors.
The log file will also contain a warning message, if there are allocated vectors left.
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Return a pointer to a new vector. The number of elements or their subdivision into blocks (if applicable) is unspecified and users of this function should reset vectors to their proper size. The same holds for the contents of vectors: they are unspecified.
Implements VectorMemory< VectorType >.
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Return a vector and indicate that it is not going to be used any further by the instance that called alloc() to get a pointer to it.
For the present class, this means retaining the vector for later reuse by the alloc() method.
Implements VectorMemory< VectorType >.
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Release all vectors that are not currently in use.
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virtual |
Memory consumed by this class and all currently allocated vectors.
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staticprivate |
Array of allocated vectors.
Definition at line 326 of file vector_memory.h.
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Overall number of allocations. Only used for bookkeeping and to generate output at the end of an object's lifetime.
Definition at line 332 of file vector_memory.h.
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Number of vectors currently allocated in this object; used for detecting memory leaks.
Definition at line 337 of file vector_memory.h.
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A flag controlling the logging of statistics by the destructor.
Definition at line 342 of file vector_memory.h.
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staticprivate |
Mutex to synchronise access to internal data of this object from multiple threads.
Definition at line 348 of file vector_memory.h.
1.8.14