diff --git a/tree/inc/TTreeFilePrefetch.h b/tree/inc/TTreeFilePrefetch.h
index c73c65e1ac9f7952532da66760cd4630943daa31..8e1b5651a6ee46b92b20abd6852cde25e1eb6b21 100644
--- a/tree/inc/TTreeFilePrefetch.h
+++ b/tree/inc/TTreeFilePrefetch.h
@@ -1,4 +1,4 @@
-// @(#)root/tree:$Name: $:$Id: TTreeFilePrefetch.h,v 1.1 2006/06/05 20:30:27 brun Exp $
+// @(#)root/tree:$Name: $:$Id: TTreeFilePrefetch.h,v 1.2 2006/06/08 12:46:45 brun Exp $
// Author: Rene Brun 04/06/2006
/*************************************************************************
@@ -30,9 +30,11 @@ class TTree;
class TTreeFilePrefetch : public TFilePrefetch {
protected:
- TTree *fTree; //!pointer to the TTree
- Long64_t fEntryMax; //last entry in the cache
-
+ TTree *fTree; //!pointer to the TTree
+ Long64_t fEntryMin; //first entry in the cache
+ Long64_t fEntryMax; //last entry in the cache
+ static Double_t fgThreshold; //do not register basket if entry-fEntrymin>fgEntryDiff
+
protected:
TTreeFilePrefetch(const TTreeFilePrefetch &); //this class cannot be copied
TTreeFilePrefetch& operator=(const TTreeFilePrefetch &);
@@ -41,11 +43,13 @@ public:
TTreeFilePrefetch();
TTreeFilePrefetch(TTree *tree, Int_t buffersize=0);
virtual ~TTreeFilePrefetch();
+ static Double_t GetThreshold();
TTree *GetTree() const {return fTree;}
virtual Bool_t ReadBuffer(char *buf, Long64_t pos, Int_t len);
Bool_t Register(Long64_t offset);
- void SetEntryMax(Long64_t emax);
+ void SetEntryRange(Long64_t emin, Long64_t emax);
void SetTree(TTree *tree);
+ static void SetThreshold(Double_t t=0.01);
ClassDef(TTreeFilePrefetch,1) //Specialization of TFilePrefetch for a TTree
};
diff --git a/tree/src/TTreeFilePrefetch.cxx b/tree/src/TTreeFilePrefetch.cxx
index 9f8e3e095d2de90ef3e19424d531e16403f4708f..14dc51ca300e7a311c11272cc84f500101b6cb54 100644
--- a/tree/src/TTreeFilePrefetch.cxx
+++ b/tree/src/TTreeFilePrefetch.cxx
@@ -1,4 +1,4 @@
-// @(#)root/tree:$Name: $:$Id: TTreeFilePrefetch.cxx,v 1.4 2006/06/08 13:26:01 brun Exp $
+// @(#)root/tree:$Name: $:$Id: TTreeFilePrefetch.cxx,v 1.5 2006/06/09 11:54:33 brun Exp $
// Author: Rene Brun 04/06/2006
/*************************************************************************
@@ -36,11 +36,14 @@
#include "TBranch.h"
#include "TLeaf.h"
+Double_t TTreeFilePrefetch::fgThreshold = 0.01;
+
ClassImp(TTreeFilePrefetch)
//______________________________________________________________________________
TTreeFilePrefetch::TTreeFilePrefetch() : TFilePrefetch(),
fTree(0),
+ fEntryMin(0),
fEntryMax(1)
{
// Default Constructor.
@@ -49,6 +52,7 @@ TTreeFilePrefetch::TTreeFilePrefetch() : TFilePrefetch(),
//______________________________________________________________________________
TTreeFilePrefetch::TTreeFilePrefetch(TTree *tree, Int_t buffersize) : TFilePrefetch(tree->GetCurrentFile(),buffersize),
fTree(tree),
+ fEntryMin(0),
fEntryMax(tree->GetEntries())
{
// Constructor.
@@ -75,6 +79,15 @@ TTreeFilePrefetch& TTreeFilePrefetch::operator=(const TTreeFilePrefetch& pf)
return *this;
}
+//_____________________________________________________________________________
+Double_t TTreeFilePrefetch::GetThreshold()
+{
+ //static function returning fgThreshold
+ //see SetThreshold
+
+ return fgThreshold;
+}
+
//_____________________________________________________________________________
Bool_t TTreeFilePrefetch::ReadBuffer(char *buf, Long64_t pos, Int_t len)
{
@@ -106,11 +119,14 @@ Bool_t TTreeFilePrefetch::Register(Long64_t offset)
// Register branch owning basket at starting position offset
// return kTRUE if the registration succeeds
+ Bool_t status = kFALSE;
+ //do not cache branches with a small hit rate
+ if ((fTree->GetReadEntry()-fEntryMin) > 100*fgThreshold) return status;
+
//reset cache when reaching the maximum cache size
if (fNtot+30000 > fBufferSize) TFilePrefetch::Prefetch(0,0);
Int_t nleaves = fTree->GetListOfLeaves()->GetEntriesFast();
//loop on all the branches to find the branch with a buffer starting at offset
- Bool_t status = kFALSE;
TBranch *branch = 0;
for (Int_t i=0;i<nleaves;i++) {
TLeaf *leaf = (TLeaf*)fTree->GetListOfLeaves()->At(i);
@@ -121,6 +137,7 @@ Bool_t TTreeFilePrefetch::Register(Long64_t offset)
Long64_t *entries = branch->GetBasketEntry();
//we have found the branch. We now register all its baskets
//from the requested offset to the basket below fEntrymax
+ Int_t ntb = 0;
for (Int_t j=0;j<nb;j++) {
if (branch->GetBasketSeek(j) == offset) {
for (Int_t k=j;k<nb;k++) {
@@ -131,24 +148,26 @@ Bool_t TTreeFilePrefetch::Register(Long64_t offset)
return status;
}
TFilePrefetch::Prefetch(pos,len);
+ ntb++;
status = kTRUE;
}
- if (gDebug > 0) printf("registering branch %s offset=%lld\n",branch->GetName(),offset);
+ if (gDebug > 0) printf("Entry: %lld, registering branch %s offset=%lld\n",fTree->GetReadEntry(),branch->GetName(),offset);
return status;
}
}
}
- if (status && branch && gDebug > 0) printf("registering branch %s offset=%lld\n",branch->GetName(),offset);
+ if (status && branch && gDebug > 0) printf("Entry: %lld, registering branch %s offset=%lld\n",fTree->GetReadEntry(),branch->GetName(),offset);
return status;
}
//_____________________________________________________________________________
-void TTreeFilePrefetch::SetEntryMax(Long64_t emax)
+void TTreeFilePrefetch::SetEntryRange(Long64_t emin, Long64_t emax)
{
- // Set the maximum entry number to be processed
+ // Set the minimum and maximum entry number to be processed
// this information helps to optimize the number of baskets to read
// when prefetching the branch buffers.
+ fEntryMin = emin;
fEntryMax = emax;
}
@@ -159,3 +178,15 @@ void TTreeFilePrefetch::SetTree(TTree *tree)
fTree = tree;
}
+
+//_____________________________________________________________________________
+void TTreeFilePrefetch::SetThreshold(Double_t t)
+{
+ // Static function to set fgThreshold
+ // A new basket will not be registered in the cache if
+ // the current (Tree entry < fEntryMin) > 100*fgThreshold
+ // so t is more or less the percentage of baskets read to be considered in the cache
+ // This algorithm eliminates branches where only a few baskets are processed
+
+ fgThreshold = t;
+}
diff --git a/treeplayer/src/TTreePlayer.cxx b/treeplayer/src/TTreePlayer.cxx
index 02d9068bbdd19df2889c55470419367c68de1c52..4fdf2bd4eebd0f41f5a4ca3f2dbaadc1682ca6c5 100644
--- a/treeplayer/src/TTreePlayer.cxx
+++ b/treeplayer/src/TTreePlayer.cxx
@@ -1,4 +1,4 @@
-// @(#)root/treeplayer:$Name: $:$Id: TTreePlayer.cxx,v 1.211 2006/06/05 20:30:28 brun Exp $
+// @(#)root/treeplayer:$Name: $:$Id: TTreePlayer.cxx,v 1.212 2006/06/08 13:26:01 brun Exp $
// Author: Rene Brun 12/01/96
/*************************************************************************
@@ -2590,7 +2590,7 @@ Long64_t TTreePlayer::Process(TSelector *selector,Option_t *option, Long64_t nen
TFile *curfile = fTree->GetCurrentFile();
if (curfile && fTree->GetCacheSize() > 0) {
TTreeFilePrefetch *tpf = (TTreeFilePrefetch*)curfile->GetFilePrefetch();
- if (tpf) tpf->SetEntryMax(firstentry+nentries);
+ if (tpf) tpf->SetEntryRange(firstentry,firstentry+nentries);
else fTree->SetCacheSize(fTree->GetCacheSize());
}