VTK  9.1.0
vtkExodusIICache.h
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1 #ifndef vtkExodusIICache_h
2 #define vtkExodusIICache_h
3 
4 // ============================================================================
5 // The following classes define an LRU cache for data arrays
6 // loaded by the Exodus reader. Here's how they work:
7 //
8 // The actual cache consists of two STL containers: a set of
9 // cache entries (vtkExodusIICacheEntry) and a list of
10 // cache references (vtkExodusIICacheRef). The entries in
11 // these containers are sorted for fast retrieval:
12 // 1. The cache entries are indexed by the timestep, the
13 // object type (edge block, face set, ...), and the
14 // object ID (if one exists). When you call Find() to
15 // retrieve a cache entry, you provide a key containing
16 // this information and the array is returned if it exists.
17 // 2. The list of cache references are stored in "least-recently-used"
18 // order. The least recently referenced array is the first in
19 // the list. Whenever you request an entry with Find(), it is
20 // moved to the back of the list if it exists.
21 // This makes retrieving arrays O(n log n) and popping LRU
22 // entries O(1). Each cache entry stores an iterator into
23 // the list of references so that it can be located quickly for
24 // removal.
25 
26 #include "vtkIOExodusModule.h" // For export macro
27 #include "vtkObject.h"
28 
29 #include <list> // use for LRU ordering
30 #include <map> // used for cache storage
31 
32 class VTKIOEXODUS_EXPORT vtkExodusIICacheKey
33 {
34 public:
35  int Time;
37  int ObjectId;
38  int ArrayId;
40  {
41  Time = -1;
42  ObjectType = -1;
43  ObjectId = -1;
44  ArrayId = -1;
45  }
46  vtkExodusIICacheKey(int time, int objType, int objId, int arrId)
47  {
48  Time = time;
49  ObjectType = objType;
50  ObjectId = objId;
51  ArrayId = arrId;
52  }
54  {
55  Time = src.Time;
56  ObjectType = src.ObjectType;
57  ObjectId = src.ObjectId;
58  ArrayId = src.ArrayId;
59  }
61  bool match(const vtkExodusIICacheKey& other, const vtkExodusIICacheKey& pattern) const
62  {
63  if (pattern.Time && this->Time != other.Time)
64  return false;
65  if (pattern.ObjectType && this->ObjectType != other.ObjectType)
66  return false;
67  if (pattern.ObjectId && this->ObjectId != other.ObjectId)
68  return false;
69  if (pattern.ArrayId && this->ArrayId != other.ArrayId)
70  return false;
71  return true;
72  }
73  bool operator<(const vtkExodusIICacheKey& other) const
74  {
75  if (this->Time < other.Time)
76  return true;
77  else if (this->Time > other.Time)
78  return false;
79  if (this->ObjectType < other.ObjectType)
80  return true;
81  else if (this->ObjectType > other.ObjectType)
82  return false;
83  if (this->ObjectId < other.ObjectId)
84  return true;
85  else if (this->ObjectId > other.ObjectId)
86  return false;
87  if (this->ArrayId < other.ArrayId)
88  return true;
89  return false;
90  }
91 };
92 
94 class vtkExodusIICache;
95 class vtkDataArray;
96 
97 typedef std::map<vtkExodusIICacheKey, vtkExodusIICacheEntry*> vtkExodusIICacheSet;
98 typedef std::map<vtkExodusIICacheKey, vtkExodusIICacheEntry*>::iterator vtkExodusIICacheRef;
99 typedef std::list<vtkExodusIICacheRef> vtkExodusIICacheLRU;
100 typedef std::list<vtkExodusIICacheRef>::iterator vtkExodusIICacheLRURef;
101 
102 class VTKIOEXODUS_EXPORT vtkExodusIICacheEntry
103 {
104 public:
108 
110 
111  vtkDataArray* GetValue() { return this->Value; }
112 
113 protected:
116 
117  friend class vtkExodusIICache;
118 };
119 
120 class VTKIOEXODUS_EXPORT vtkExodusIICache : public vtkObject
121 {
122 public:
124  vtkTypeMacro(vtkExodusIICache, vtkObject);
125  void PrintSelf(ostream& os, vtkIndent indent) override;
126 
128  void Clear();
129 
132  void SetCacheCapacity(double sizeInMiB);
133 
138  double GetSpaceLeft() { return this->Capacity - this->Size; }
139 
143  int ReduceToSize(double newSize);
144 
147 
152 
158 
169 
170 protected:
173 
175  ~vtkExodusIICache() override;
176 
179 
181  double Capacity;
182 
185  double Size;
186 
194 
197 
198 private:
199  vtkExodusIICache(const vtkExodusIICache&) = delete;
200  void operator=(const vtkExodusIICache&) = delete;
201 };
202 #endif // vtkExodusIICache_h
abstract superclass for arrays of numeric data
Definition: vtkDataArray.h:50
vtkExodusIICacheEntry(vtkDataArray *arr)
vtkDataArray * GetValue()
vtkExodusIICacheLRURef LRUEntry
vtkExodusIICacheEntry(const vtkExodusIICacheEntry &other)
bool operator<(const vtkExodusIICacheKey &other) const
vtkExodusIICacheKey & operator=(const vtkExodusIICacheKey &src)=default
bool match(const vtkExodusIICacheKey &other, const vtkExodusIICacheKey &pattern) const
vtkExodusIICacheKey(int time, int objType, int objId, int arrId)
vtkExodusIICacheKey(const vtkExodusIICacheKey &src)
void Clear()
Empty the cache.
void SetCacheCapacity(double sizeInMiB)
Set the maximum allowable cache size.
vtkExodusIICacheLRU LRU
The actual LRU list (indices into the cache ordered least to most recently used).
double Size
The current size of the cache (i.e., the size of the all the arrays it currently contains) in MiB.
void PrintSelf(ostream &os, vtkIndent indent) override
Methods invoked by print to print information about the object including superclasses.
vtkExodusIICache()
Default constructor.
double Capacity
The capacity of the cache (i.e., the maximum size of all arrays it contains) in MiB.
int Invalidate(const vtkExodusIICacheKey &key)
Invalidate a cache entry (drop it from the cache) if the key exists.
int ReduceToSize(double newSize)
Remove cache entries until the size of the cache is at or below the given size.
static vtkExodusIICache * New()
~vtkExodusIICache() override
Destructor.
void RecomputeSize()
Avoid (some) FP problems.
double GetSpaceLeft()
See how much cache space is left.
void Insert(vtkExodusIICacheKey &key, vtkDataArray *value)
Insert an entry into the cache (this can remove other cache entries to make space).
vtkDataArray *& Find(const vtkExodusIICacheKey &)
Determine whether a cache entry exists.
vtkExodusIICacheSet Cache
A least-recently-used (LRU) cache to hold arrays.
int Invalidate(const vtkExodusIICacheKey &key, const vtkExodusIICacheKey &pattern)
Invalidate all cache entries matching a specified pattern, dropping all matches from the cache.
a simple class to control print indentation
Definition: vtkIndent.h:34
abstract base class for most VTK objects
Definition: vtkObject.h:63
@ key
Definition: vtkX3D.h:263
@ value
Definition: vtkX3D.h:226
@ time
Definition: vtkX3D.h:503
std::list< vtkExodusIICacheRef > vtkExodusIICacheLRU
std::map< vtkExodusIICacheKey, vtkExodusIICacheEntry * >::iterator vtkExodusIICacheRef
std::map< vtkExodusIICacheKey, vtkExodusIICacheEntry * > vtkExodusIICacheSet
std::list< vtkExodusIICacheRef >::iterator vtkExodusIICacheLRURef