内存池VC实现 VC十年技术群聊天笔记

以下内容摘自VC十年技术群, 欢迎内存池技术研究人员进本群, 共同研究技术.

 

也许以下的代码实现, 并不完美的, 也不是优秀, 但能解决实际问题, 可以证明是有效果的.
无论如何, 也是提供了一个非常好的参考.

以此鼓励不断为性能为内存使用烦恼的VC技术人员.

 

 本文出自: 阿呆 http://blog.csdn.net/davemin
宣传: VC 十年技术群 30107096 欢迎高手加入,本群只研究VC

 

(2009-10-16 11:06:01)   张鹏-宁波(52401692)
命中率90%多，呵呵。目前看上去运行可以到一个月左右，比较稳定，哈哈
(2009-10-16 11:06:06)   张鹏-宁波(52401692)
原来只能运行2天左右

 

(2009-10-16 11:08:12)   张鹏-宁波(52401692)
其实我那个思路就更菜了，呵呵。但效果还很不错，就是固定了几个大小，16、32、64、128 ……

 

(2009-10-16 11:11:03)   阿呆 -假装高手(40133435)
固定了几个大小，16、32、64、128 …… 这样的设计,其实是大多小型内存池实现的基本方法.
(2009-10-16 11:11:19)   阿呆 -假装高手(40133435)
stl 也是如此.
(2009-10-16 11:11:32)   阿呆 -假装高手(40133435)
不管怎么实现,关键是管不管用. 
(2009-10-16 11:13:17)   ...(115963176)
说的这样HAPPY，代码贴出来
大家学习一下啊
 

(2009-10-16 11:16:57)   张鹏-宁波(52401692)

#pragma oncestruct MEM_BLOCK{ void * m_pData; size_t m_nUsedSize; MEM_BLOCK () { m_pData = NULL; m_nUsedSize = 0; }};typedef CMap <void *, void * &, MEM_BLOCK, MEM_BLOCK &> CMemMap;

// TODO:
// 1、设置每个Pool的单独的上限
// 2、如果总的内存占用太多了，要尽快释放

class CMemoryPool{public: CMemoryPool (size_t nBlockSize); ~CMemoryPool (); void * New (const size_t nSize); void Delete (const void* pValue, size_t nSize); size_t GetBlockSize () { return m_blockSize; };private: void FreeSpace (); size_t m_blockSize; CMemMap m_memMap; CArray <MEM_BLOCK, MEM_BLOCK &> m_freeArray; CCriticalSection m_cs; void TraceInfo ();};class CMemory{public: CMemory (); ~CMemory (); void Init (); void * New (const size_t nSize); void Delete (void* pValue, size_t nSize);private: void AddPool (const size_t nBlockSize); CMemoryPool * GetPool (size_t nSize); size_t m_minSize; size_t m_maxSize; CArray <CMemoryPool *, CMemoryPool * &> m_poolArray;};

 

 本文出自: 阿呆 http://blog.csdn.net/davemin
宣传: VC 十年技术群 30107096 欢迎高手加入,本群只研究VC

(2009-10-16 11:18:45)   张鹏-宁波(52401692)
CMemoryPool::CMemoryPool (size_t nBlockSize){ m_blockSize = nBlockSize;}CMemoryPool::~CMemoryPool (){ ASSERT (m_memMap.IsEmpty ()); while (!m_freeArray.IsEmpty ()) { MEM_BLOCK block = m_freeArray.GetAt (m_freeArray.GetCount () - 1); ASSERT (block.m_pData != NULL && block.m_nUsedSize == 0 ); if (block.m_pData != NULL) free (block.m_pData); m_freeArray.RemoveAt (m_freeArray.GetCount () - 1); }}void* CMemoryPool::New (const size_t nSize){ ASSERT (nSize <= m_blockSize && nSize > 0); MEM_BLOCK block; CSingleLock lock (&m_cs); lock.Lock (); if (!m_freeArray.IsEmpty ()) { block = m_freeArray.GetAt (m_freeArray.GetCount () - 1); ASSERT (block.m_pData != NULL && block.m_nUsedSize == 0 );#ifdef _DEBUG MEM_BLOCK b; ASSERT (!m_memMap.Lookup (block.m_pData, b));#endif m_freeArray.RemoveAt (m_freeArray.GetCount () - 1); } else { ASSERT (block.m_pData == NULL && block.m_nUsedSize == 0); block.m_pData = malloc (m_blockSize); } block.m_nUsedSize = nSize; m_memMap.SetAt (block.m_pData, block); FreeSpace (); return block.m_pData;}void CMemoryPool::Delete (const void* pValue, size_t nSize){ ASSERT (nSize <= m_blockSize && nSize > 0); MEM_BLOCK block; void * pKey = (void *)pValue; CSingleLock lock (&m_cs); lock.Lock (); ASSERT (!m_memMap.IsEmpty ()); if (m_memMap.IsEmpty ()) return; BOOL b = m_memMap.Lookup ((void *)pKey, block); ASSERT (b); if (b && block.m_pData != NULL) { ASSERT (block.m_pData == pValue && block.m_nUsedSize == nSize); m_memMap.RemoveKey (pKey); block.m_nUsedSize = 0; m_freeArray.Add (block); } FreeSpace ();}void CMemoryPool::FreeSpace (){ MEM_BLOCK block; CSingleLock lock (&m_cs); lock.Lock (); ASSERT (! (m_freeArray.GetCount () > 1024 && (m_freeArray.GetCount () + m_memMap.GetCount () ) * m_blockSize >= 1024 * 1024 * 1024) ); BOOL bNeedFree = (m_freeArray.GetCount () >= 2048 || (m_freeArray.GetCount () >= 10 && m_blockSize >= 512 * 1024)); if (!bNeedFree) { TraceInfo (); return; } // 如果需要释放了，则尽可能多的释放一些，以便释放出一些大的空间出来。正在使用的空间到时候也肯定会再还回来。 while (m_freeArray.GetCount () >= 1536 || (m_freeArray.GetCount () >= 10 && m_blockSize >= 512 * 1024)) { block = m_freeArray.GetAt (m_freeArray.GetCount () - 1); ASSERT (block.m_pData != NULL && block.m_nUsedSize == 0 ); if (block.m_pData != NULL) { free (block.m_pData); #ifdef DLBT_INFO m_realDelCount ++; #endif } m_freeArray.RemoveAt (m_freeArray.GetCount () - 1); } TraceInfo ();}void CMemoryPool::TraceInfo (){}

 

 

 

 

(2009-10-16 11:18:57)   张鹏-宁波(52401692)
//////// CMemory //////// 常用的Pool的Sizesize_t g_memPoolSizes [] = { 8, 16, 64, 128, 256, 1024, 4 * 1024, 16 * 1024 + 20, 32 * 1024, 64 * 1024, 128 * 1024, 256 * 1024, 512 * 1024, 1024 * 1024, 2048 * 1024, 4096 * 1024};CMemory::CMemory (){ m_minSize = -1; m_maxSize = 0;}CMemory::~CMemory (){ for (int i = 0; i < m_poolArray.GetSize (); i ++) { CMemoryPool * pool = m_poolArray.GetAt (i); ASSERT (pool != NULL); delete pool; } m_poolArray.RemoveAll ();}// 初始化常用的Pool，根据不同的程序的需要，调整该函数中的Pool的参数void CMemory::Init (){ for (int i = 0; i < sizeof (g_memPoolSizes) / sizeof (g_memPoolSizes [0]); i ++) { AddPool (g_memPoolSizes [i]); }}void CMemory::AddPool (const size_t nBlockSize){#ifdef _DEBUG for (int i = 0; i < m_poolArray.GetSize (); i ++) { CMemoryPool * pool = m_poolArray.GetAt (i); ASSERT (pool != NULL); ASSERT (pool->GetBlockSize () != nBlockSize); }#endif ASSERT (nBlockSize < 1024 * 1024 * 8); if (m_minSize > nBlockSize) m_minSize = nBlockSize; if (m_maxSize < nBlockSize) m_maxSize = nBlockSize; CMemoryPool * pool = new CMemoryPool (nBlockSize); ASSERT (pool != NULL); if (pool != NULL) { m_poolArray.Add (pool); }}void * CMemory::New (const size_t nSize){ if (nSize == 0) return NULL; CMemoryPool * pool = GetPool (nSize); if (pool == NULL) return malloc (nSize); return pool->New (nSize);}void CMemory::Delete (void* pValue, size_t nSize){ if (nSize == 0) return; CMemoryPool * pool = GetPool (nSize); if (pool == NULL) return free (pValue); return pool->Delete (pValue, nSize);}CMemoryPool * CMemory::GetPool (size_t nSize){ if (nSize == 0 || nSize > m_maxSize) return NULL; for (int i = 0; i < sizeof (g_memPoolSizes) / sizeof (g_memPoolSizes [0]); i ++) { if (nSize <= g_memPoolSizes [i]) return m_poolArray.GetAt (i); } ASSERT (FALSE); return NULL;}

 

 
(2009-10-16 11:19:04)   张鹏-宁波(52401692)
就这些了，呵呵，欢迎拍砖
(2009-10-16 11:19:58)   张鹏-宁波(52401692)
用法很简单，呵呵，就是将普通的new改为调用 CMemory的New, delete改为调用 CMemory的Delete
(2009-10-16 11:20:23)   张鹏-宁波(52401692)
CMemory中管理好多个小池子，分大小的，它会找到合适的池子去New和Delete
(2009-10-16 11:21:41)   张鹏-宁波(52401692)
如果池子中没有空位，就真的new，否则就用一个空位，释放时也不真释放，只是标记一下，放到池子里面。根据我程序的特性，我用了这么多大小的池子，好像是16个池子，管理的内存块大小分别是：

size_t g_memPoolSizes [] = { 8, 16, 64, 128, 256, 1024, 4 * 1024, 16 * 1024 + 20, 32 * 1024, 64 * 1024, 128 * 1024, 256 * 1024, 512 * 1024, 1024 * 1024, 2048 * 1024, 4096 * 1024};