--- trunk/OOPSE-2.0/src/brains/BlockSnapshotManager.cpp	2005/02/13 08:05:33	2006
+++ trunk/OOPSE-2.0/src/brains/BlockSnapshotManager.cpp	2005/02/17 15:18:36	2042
@@ -40,112 +40,173 @@
  */
 #include <algorithm>
 #include "brains/BlockSnapshotManager.hpp"
+#include "utils/residentMem.h"
 #include "utils/physmem.h"
+#include "utils/Algorithm.hpp"
 #include "brains/SimInfo.hpp"
 #include "io/DumpReader.hpp"
 
 namespace oopse {
 BlockSnapshotManager::BlockSnapshotManager(SimInfo* info, const std::string& filename, 
     int storageLayout, int blockCapacity) 
-    : SnapshotManager(storageLayout), info_(info), 
-      blockCapacity_(blockCapacity), activeBlocks(blockCapacity_, -1) {
+    : SnapshotManager(storageLayout), info_(info), blockCapacity_(blockCapacity), 
+      activeBlocks_(blockCapacity_, -1), activeRefCount_(blockCapacity_, 0) {
 
     nAtoms_ = info->getNGlobalAtoms();
     nRigidBodies_ = info->getNGlobalRigidBodies();
 
-    double avalPhysMem = physmem_available();
+    double physMem = physmem_total();
+    double rssMem = residentMem();
+    double avaliablePhysMem = physMem - rssMem;
     
     int bytesPerStuntDouble = DataStorage::getBytesPerStuntDouble(storageLayout);
 
-    int bytesPerFrame = nStuntDoubles * bytesPerStuntDouble;
+    int bytesPerFrame = (nRigidBodies_ + nAtoms_) * bytesPerStuntDouble;
 
-    int frameCapacity = int (avalPhysMem / bytesPerFrame);
+    int frameCapacity = int (avaliablePhysMem / bytesPerFrame);
     
     nSnapshotPerBlock_ = frameCapacity /blockCapacity_ ;
-
     reader_ = new DumpReader(info, filename);
-    nframes_ = reader->getNFrames();
+    nframes_ = reader_->getNFrames();
 
-    int nblocks = nframes / nSnapshotPerBlock_;
-    if (nframes % nSnapshotPerBlock != 0) {
+    int nblocks = nframes_ / nSnapshotPerBlock_;
+    if (nframes_ % nSnapshotPerBlock_ != 0) {
         ++nblocks;
     }  
     
     for (int i = 0; i < nblocks; ++i) {
-        blocks_.push_back(SnapshotBlock(i, (i+1)*nSnapshotPerBlock_);    
+        blocks_.push_back(SnapshotBlock(i*nSnapshotPerBlock_, (i+1)*nSnapshotPerBlock_));    
     }
     //the last block may not have nSnapshotPerBlock frames, we need to consider this special situation
-    blocks.back.second = nframes;
+    blocks_.back().second = nframes_;
 
-    snapshots_.insert(snapshot_.begin(), nframes, NULL);   
+    snapshots_.insert(snapshots_.begin(), nframes_, static_cast<Snapshot*>(NULL));   
+
+    std::cout << "physmem = " << int(physMem) << "\trssMem =  "<< int(rssMem) << "\t availablePhysMem = " << int(avaliablePhysMem) <<std::endl;
+    std::cout << "nSnapshotPerBlock = " << nSnapshotPerBlock_ << "\t total block = " << nblocks << std::endl;
     
 }
 
 
-BlockSnapshotMananger::~BlockSnapshotMananger() {
+BlockSnapshotManager::~BlockSnapshotManager() {
     currentSnapshot_ = NULL;
     previousSnapshot_ = NULL;
     
     delete reader_;
-    std::for_each(activeBlocks_.begin(), activeBlocks_.end(), unloadBlock);
+
+    std::vector<int>::iterator i;
+    for (i = activeBlocks_.begin(); i != activeBlocks_.end(); ++i) {
+        if (*i != -1) {
+            unloadBlock(*i);
+        }
+    }
 }
 
 int BlockSnapshotManager::getNActiveBlocks() {
-    return std::count_if(activeBlocks_.begin(), activeBlocks_.end(), std::not);
+#ifdef __RWSTD   
+    int count = 0;
+    std::count_if(activeBlocks_.begin(), activeBlocks_.end(), std::bind2nd(std::not_equal_to<int>(), -1), count);
+    return count;
+#else
+    return std::count_if(activeBlocks_.begin(), activeBlocks_.end(), std::bind2nd(std::not_equal_to<int>(), -1));
+#endif
 }
 
-bool BlockSnapshotManager::isBlockActive(int block) {
-    return std::find(activeBlocks_.begin(), activeBlocks_.end(), block) != activeBlocks_.end() ? true : false;
-}
 
+
 bool BlockSnapshotManager::loadBlock(int block) {
+    std::vector<int>::iterator i = findActiveBlock(block);
     bool loadSuccess;
-    if (isBlockActive(block)) {
+    if (i != activeBlocks_.end()) {
+        //if block is already in memory, just increast the reference count
+        ++activeRefCount_[i - activeBlocks_.begin()];
         loadSuccess = true;
     } else if (getNActiveBlocks() < blockCapacity_){
-
-        for (int i = blocks_[block].first; i < blocks_[block].second; ++i) {
-            snapshots_[i] = loadFrame(i);
-        }
-        
-        std::vector<int>::iterator j;
-        j = std::find(activeBlocks_.begin(), activeBlocks_.end(), -1);
-        assert(j != activeBlocks_.end());
-        *j = block;    
+        //if number of active blocks is less than the block capacity, just load it
+        internalLoad(block);
         loadSuccess = true;
-    }else {
+    } else if (hasZeroRefBlock() > 0) {
+        //if already reach the block capacity, need to unload a block with 0 reference
+        int zeroRefBlock = getFirstZeroRefBlock();
+        assert(zeroRefBlock != -1);
+        internalUnload(zeroRefBlock);
+        internalLoad(block);
+    } else {
+        //reach the capacity and all blocks in memory are not zero reference
         loadSuccess = false;
     }
-
+    
     return loadSuccess;
 }
 
 bool BlockSnapshotManager::unloadBlock(int block) {
     bool unloadSuccess;
-    if (!isBlockActive(block)){
-        unloadSuccess = false;
-    } else {
-        for (int i = blocks_[block].first; i < blocks_[block].second; ++i) {
-            delete snapshots_[i];
-            snapshots_[i] = NULL;
+    std::vector<int>::iterator i = findActiveBlock(block);
+    
+    if (i != activeBlocks_.end()){
+        --activeRefCount_[i - activeBlocks_.begin()];
+        if (activeRefCount_[i - activeBlocks_.begin()] < 0) {
+            //in case, unloadBlock called multiple times
+            activeRefCount_[i - activeBlocks_.begin()]  = 0;
         }
-        std::vector<int>::iterator j;
-        j = std::find(activeBlocks_.begin(), activeBlocks_.end(), block);
-        assert(j != activeBlocks_.end());
-        *j = -1;
+        
+        unloadSuccess = true;
+    } else {
+        unloadSuccess = false;
     }
+
+    return unloadSuccess;
 }
 
+void BlockSnapshotManager::internalLoad(int block) {
+        
+    for (int i = blocks_[block].first; i < blocks_[block].second; ++i) {
+        snapshots_[i] = loadFrame(i);
+    }
+    
+    std::vector<int>::iterator j;
+    j = std::find(activeBlocks_.begin(), activeBlocks_.end(), -1);
+    assert(j != activeBlocks_.end());
+    *j = block;    
+    ++activeRefCount_[j - activeBlocks_.begin()];
+}
+
+void BlockSnapshotManager::internalUnload(int block) {
+    for (int i = blocks_[block].first; i < blocks_[block].second; ++i) {
+        delete snapshots_[i];
+        snapshots_[i] = NULL;
+    }
+    std::vector<int>::iterator j;
+    j = std::find(activeBlocks_.begin(), activeBlocks_.end(), block);
+    assert(j != activeBlocks_.end());
+    *j = -1;
+}
+
+bool BlockSnapshotManager::hasZeroRefBlock(){
+    return std::find(activeRefCount_.begin(), activeRefCount_.end(), 0) != activeRefCount_.end() ?  true : false;
+}
+
+int BlockSnapshotManager::getFirstZeroRefBlock(){
+     std::vector<int>::iterator i = std::find(activeRefCount_.begin(), activeRefCount_.end(), 0);
+     return i != activeRefCount_.end() ? activeBlocks_[i - activeRefCount_.begin()] : -1;
+}
+
 std::vector<int> BlockSnapshotManager::getActiveBlocks() {
     std::vector<int> result;
-    std::copy_if(activeBlocks_.begin(), activeBlocks_.end());
+    oopse::copy_if(activeBlocks_.begin(), activeBlocks_.end(), std::back_inserter(result), 
+        std::bind2nd(std::not_equal_to<int>(), -1));
+    return result;    
 }
 
 Snapshot* BlockSnapshotManager::loadFrame(int frame){
     Snapshot* snapshot = new Snapshot(nAtoms_, nRigidBodies_, getStorageLayout());
     snapshot->setID(frame);
-    setCurrentSnapshot(snapshot);   /** @todo fixed me */
+    
+    /** @todo fixed me */
+    Snapshot* oldSnapshot = currentSnapshot_;
+    currentSnapshot_ = snapshot;   
     reader_->readFrame(frame);
+    currentSnapshot_ = oldSnapshot;
     return snapshot;
 }