TTreePerfStats.cxx

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// @(#)root/treeplayer:$Id$
// Author: Rene Brun 29/10/09

/*************************************************************************
 * Copyright (C) 1995-2009, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

/** \class TTreePerfStats

TTree I/O performance measurement. see example of use below.

The function FileReadEvent is called from TFile::ReadBuffer.
For each call the following information is stored in fGraphIO
 -  x[i]  = Tree entry number
 -  y[i]  = 1e-6*(file position)
 -  ey[i] = 1e-9*number of bytes read
For each call the following information is stored in fGraphTime
 -  x[i]  = Tree entry number
 -  y[i]  = Time now
 -  ey[i] = readtime, eg timenow - start
The TTreePerfStats object can be saved in a ROOT file in such a way that
its inspection can be done outside the job that generated it.

Example of use:
~~~{.cpp}
{
  TFile *f = TFile::Open("RelValMinBias-GEN-SIM-RECO.root");
  T = (TTree*)f->Get("Events");
  Long64_t nentries = T->GetEntries();
  T->SetCacheSize(10000000);
  T->SetCacheEntryRange(0,nentries);
  T->AddBranchToCache("*");
//
  TTreePerfStats *ps= new TTreePerfStats("ioperf",T);
//
  for (Int_t i=0;i<nentries;i++) {
     T->GetEntry(i);
  }
  ps->SaveAs("cmsperf.root");
}
~~~
then, in a root interactive session, one can do:
~~~{.cpp}
   root > TFile f("cmsperf.root");
   root > ioperf->Draw();
   root > ioperf->Print();
~~~
The Draw or Print functions print the following information:
 -  TreeCache = TTree cache size in MBytes
 -  N leaves  = Number of leaves in the TTree
 -  ReadTotal = Total number of zipped bytes read
 -  ReadUnZip = Total number of unzipped bytes read
 -  ReadCalls = Total number of disk reads
 -  ReadSize  = Average read size in KBytes
 -  Readahead = Readahead size in KBytes
 -  Readextra = Readahead overhead in percent
 -  Real Time = Real Time in seconds
 -  CPU  Time = CPU Time in seconds
 -  Disk Time = Real Time spent in pure raw disk IO
 -  Disk IO   = Raw disk IO speed in MBytes/second
 -  ReadUZRT  = Unzipped MBytes per RT second
 -  ReadUZCP  = Unipped MBytes per CP second
 -  ReadRT    = Zipped MBytes per RT second
 -  ReadCP    = Zipped MBytes per CP second

 ### NOTE 1 :
The ReadTotal value indicates the effective number of zipped bytes
returned to the application. The physical number of bytes read
from the device (as measured for example with strace) is
ReadTotal +ReadTotal*Readextra/100. Same for ReadSize.

 ### NOTE 2 :
A consequence of NOTE1, the Disk I/O speed corresponds to the effective
number of bytes returned to the application per second.
The Physical disk speed is DiskIO + DiskIO*ReadExtra/100.
*/

#include "TTreePerfStats.h"
#include "TROOT.h"
#include "TSystem.h"
#include "Riostream.h"
#include "TFile.h"
#include "TTree.h"
#include "TAxis.h"
#include "TBrowser.h"
#include "TVirtualPad.h"
#include "TPaveText.h"
#include "TGraphErrors.h"
#include "TStopwatch.h"
#include "TGaxis.h"
#include "TTimeStamp.h"
#include "TDatime.h"
#include "TMath.h"

ClassImp(TTreePerfStats);

////////////////////////////////////////////////////////////////////////////////
/// default constructor (used when reading an object only)

TTreePerfStats::TTreePerfStats() : TVirtualPerfStats()
{
   fName      = "";
   fHostInfo  = "";
   fTree      = 0;
   fNleaves   = 0;
   fFile      = 0;
   fGraphIO   = 0;
   fGraphTime = 0;
   fWatch     = 0;
   fPave      = 0;
   fTreeCacheSize = 0;
   fReadCalls     = 0;
   fReadaheadSize = 0;
   fBytesRead     = 0;
   fBytesReadExtra= 0;
   fRealNorm      = 0;
   fRealTime      = 0;
   fCpuTime       = 0;
   fDiskTime      = 0;
   fUnzipTime     = 0;
   fCompress      = 0;
   fRealTimeAxis  = 0;
   fHostInfoText  = 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Create a TTree I/O perf stats object.

TTreePerfStats::TTreePerfStats(const char *name, TTree *T) : TVirtualPerfStats()
{
   fName   = name;
   fTree   = T;
   T->SetPerfStats(this);
   fNleaves= T->GetListOfLeaves()->GetEntries();
   fFile   = T->GetCurrentFile();
   fGraphIO  = new TGraphErrors(0);
   fGraphIO->SetName("ioperf");
   fGraphIO->SetTitle(Form("%s/%s",fFile->GetName(),T->GetName()));
   fGraphIO->SetUniqueID(999999999);
   fGraphTime = new TGraphErrors(0);
   fGraphTime->SetLineColor(kRed);
   fGraphTime->SetName("iotime");
   fGraphTime->SetTitle("Real time vs entries");
   fWatch  = new TStopwatch();
   fWatch->Start();
   fPave  = 0;
   fTreeCacheSize = 0;
   fReadCalls     = 0;
   fReadaheadSize = 0;
   fBytesRead     = 0;
   fBytesReadExtra= 0;
   fRealNorm      = 0;
   fRealTime      = 0;
   fCpuTime       = 0;
   fDiskTime      = 0;
   fUnzipTime     = 0;
   fRealTimeAxis  = 0;
   fCompress      = (T->GetTotBytes()+0.00001)/T->GetZipBytes();

   Bool_t isUNIX = strcmp(gSystem->GetName(), "Unix") == 0;
   if (isUNIX)
      fHostInfo = gSystem->GetFromPipe("uname -a");
   else
      fHostInfo = "Windows ";
   fHostInfo.Resize(20);
   fHostInfo += TString::Format("ROOT %s, Git: %s", gROOT->GetVersion(), gROOT->GetGitCommit());
   TDatime dt;
   fHostInfo += TString::Format(" %s",dt.AsString());
   fHostInfoText   = 0;

   gPerfStats = this;
}

////////////////////////////////////////////////////////////////////////////////
/// Destructor

TTreePerfStats::~TTreePerfStats()
{
   fTree = 0;
   fFile = 0;
   delete fGraphIO;
   delete fGraphTime;
   delete fPave;
   delete fWatch;
   delete fRealTimeAxis;
   delete fHostInfoText;

   if (gPerfStats == this) {
      gPerfStats = 0;
   }
}


////////////////////////////////////////////////////////////////////////////////
/// Browse

void TTreePerfStats::Browse(TBrowser * /*b*/)
{
   Draw();
   gPad->Update();
}

////////////////////////////////////////////////////////////////////////////////
/// Return distance to one of the objects in the TTreePerfStats

Int_t TTreePerfStats::DistancetoPrimitive(Int_t px, Int_t py)
{
   const Int_t kMaxDiff = 7;
   Int_t puxmin = gPad->XtoAbsPixel(gPad->GetUxmin());
   Int_t puymin = gPad->YtoAbsPixel(gPad->GetUymin());
   Int_t puxmax = gPad->XtoAbsPixel(gPad->GetUxmax());
   Int_t puymax = gPad->YtoAbsPixel(gPad->GetUymax());
   if (py < puymax) return 9999;
   //on the fGraphIO ?
   Int_t distance = fGraphIO->DistancetoPrimitive(px,py);
   if (distance <kMaxDiff) {if (px > puxmin && py < puymin) gPad->SetSelected(fGraphIO); return distance;}
   // on the fGraphTime ?
   distance = fGraphTime->DistancetoPrimitive(px,py);
   if (distance <kMaxDiff) {if (px > puxmin && py < puymin) gPad->SetSelected(fGraphTime); return distance;}
   // on the pave ?
   distance = fPave->DistancetoPrimitive(px,py);
   if (distance <kMaxDiff) {gPad->SetSelected(fPave);  return distance;}
   // on the real time axis ?
   distance = fRealTimeAxis->DistancetoPrimitive(px,py);
   if (distance <kMaxDiff) {gPad->SetSelected(fRealTimeAxis);  return distance;}
   // on the host info label ?
   distance = fHostInfoText->DistancetoPrimitive(px,py);
   if (distance <kMaxDiff) {gPad->SetSelected(fHostInfoText);  return distance;}
   if (px > puxmax-300) return 2;
   return 999;
}

////////////////////////////////////////////////////////////////////////////////
/// Draw the TTree I/O perf graph.
/// by default the graph is drawn with option "al"
/// Specify option ="ap" to show only the read blocks and not the line
/// connecting the blocks

void TTreePerfStats::Draw(Option_t *option)
{
   Finish();

   TString opt = option;
   if (strlen(option)==0) opt = "al";
   opt.ToLower();
   if (gPad) {
      if (!gPad->IsEditable()) gROOT->MakeDefCanvas();
      //the following statement is necessary in case one attempts to draw
      //a temporary histogram already in the current pad
      if (TestBit(kCanDelete)) gPad->GetListOfPrimitives()->Remove(this);
   } else {
      gROOT->MakeDefCanvas();
   }
   if (opt.Contains("a")) {
      gPad->SetLeftMargin(0.35);
      gPad->Clear();
      gPad->SetGridx();
      gPad->SetGridy();
   }
   AppendPad(opt.Data());
}

////////////////////////////////////////////////////////////////////////////////
/// Return distance to one of the objects in the TTreePerfStats

void TTreePerfStats::ExecuteEvent(Int_t /*event*/, Int_t /*px*/, Int_t /*py*/)
{
}

////////////////////////////////////////////////////////////////////////////////
/// Record TTree file read event.
/// -  start is the TimeStamp before reading
/// -  len is the number of bytes read

void TTreePerfStats::FileReadEvent(TFile *file, Int_t len, Double_t start)
{
   if (file == this->fFile){
      Long64_t offset = file->GetRelOffset();
      Int_t np = fGraphIO->GetN();
      Int_t entry = fTree->GetReadEntry();
      fGraphIO->SetPoint(np,entry,1e-6*offset);
      fGraphIO->SetPointError(np,0.001,1e-9*len);
      Double_t tnow = TTimeStamp();
      Double_t dtime = tnow-start;
      fDiskTime += dtime;
      fGraphTime->SetPoint(np,entry,tnow);
      fGraphTime->SetPointError(np,0.001,dtime);
      fReadCalls++;
      fBytesRead += len;
   }
}


////////////////////////////////////////////////////////////////////////////////
/// Record TTree unzip event.
/// -  start is the TimeStamp before unzip
/// -  pos is where in the file the compressed buffer came from
/// -  complen is the length of the compressed buffer
/// -  objlen is the length of the de-compressed buffer

void TTreePerfStats::UnzipEvent(TObject * tree, Long64_t /* pos */, Double_t start, Int_t /* complen */, Int_t /* objlen */)
{
   if (tree == this->fTree){
      Double_t tnow = TTimeStamp();
      Double_t dtime = tnow-start;
      fUnzipTime += dtime;
   }
}

////////////////////////////////////////////////////////////////////////////////
/// When the run is finished this function must be called
/// to save the current parameters in the file and Tree in this object
/// the function is automatically called by Draw and Print

void TTreePerfStats::Finish()
{
   if (fRealNorm)   return;  //has already been called
   if (!fFile)      return;
   if (!fTree)      return;
   fTreeCacheSize = fTree->GetCacheSize();
   fReadaheadSize = TFile::GetReadaheadSize();
   fBytesReadExtra= fFile->GetBytesReadExtra();
   fRealTime      = fWatch->RealTime();
   fCpuTime       = fWatch->CpuTime();
   Int_t npoints  = fGraphIO->GetN();
   if (!npoints) return;
   Double_t iomax = TMath::MaxElement(npoints,fGraphIO->GetY());
   fRealNorm      = iomax/fRealTime;
   fGraphTime->GetY()[0] = fRealNorm*fGraphTime->GetEY()[0];
   // we normalize the fGraphTime such that it can be drawn on top of fGraphIO
   for (Int_t i=1;i<npoints;i++) {
      fGraphTime->GetY()[i]   = fGraphTime->GetY()[i-1] +fRealNorm*fGraphTime->GetEY()[i];
      fGraphTime->GetEY()[i]  = 0;
   }
}


////////////////////////////////////////////////////////////////////////////////
/// Draw the TTree I/O perf graph.

void TTreePerfStats::Paint(Option_t *option)
{
   Int_t npoints  = fGraphIO->GetN();
   if (!npoints) return;
   Double_t iomax = fGraphIO->GetY()[npoints-1];
   Double_t toffset=1;
   if (iomax >= 1e9) toffset = 1.2;
   fGraphIO->GetXaxis()->SetTitle("Tree entry number");
   fGraphIO->GetYaxis()->SetTitle("file position (MBytes)  ");
   fGraphIO->GetYaxis()->SetTitleOffset(toffset);
   fGraphIO->GetXaxis()->SetLabelSize(0.03);
   fGraphIO->GetYaxis()->SetLabelSize(0.03);
   fGraphIO->Paint(option);

   TString opts(option);
   opts.ToLower();
   Bool_t unzip = opts.Contains("unzip");

   //superimpose the time info (max 10 points)
   if (fGraphTime) {
      fGraphTime->Paint("l");
      TText tdisk(fGraphTime->GetX()[npoints-1],1.1*fGraphTime->GetY()[npoints-1],"RAW IO");
      tdisk.SetTextAlign(31);
      tdisk.SetTextSize(0.03);
      tdisk.SetTextColor(kRed);
      tdisk.Paint();
      if (!fRealTimeAxis) {
         Double_t uxmax = gPad->GetUxmax();
         Double_t uymax = gPad->GetUymax();
         Double_t rtmax = uymax/fRealNorm;
         fRealTimeAxis = new TGaxis(uxmax,0,uxmax,uymax,0.,rtmax,510,"+L");
         fRealTimeAxis->SetName("RealTimeAxis");
         fRealTimeAxis->SetLineColor(kRed);
         fRealTimeAxis->SetTitle("RealTime (s)  ");
         fRealTimeAxis->SetTitleColor(kRed);
         toffset = 1;
         if (fRealTime >=  100) toffset = 1.2;
         if (fRealTime >= 1000) toffset = 1.4;
         fRealTimeAxis->SetTitleOffset(toffset);
         fRealTimeAxis->SetLabelSize(0.03);
         fRealTimeAxis->SetLabelColor(kRed);
      }
      fRealTimeAxis->Paint();
   }

   Double_t extra = 100.*fBytesReadExtra/fBytesRead;
   if (!fPave) {
      fPave = new TPaveText(.01,.10,.24,.90,"brNDC");
      fPave->SetTextAlign(12);
      fPave->AddText(Form("TreeCache = %d MB",fTreeCacheSize/1000000));
      fPave->AddText(Form("N leaves  = %d",fNleaves));
      fPave->AddText(Form("ReadTotal = %g MB",1e-6*fBytesRead));
      fPave->AddText(Form("ReadUnZip = %g MB",1e-6*fBytesRead*fCompress));
      fPave->AddText(Form("ReadCalls = %d",fReadCalls));
      fPave->AddText(Form("ReadSize  = %7.3f KB",0.001*fBytesRead/fReadCalls));
      fPave->AddText(Form("Readahead = %d KB",fReadaheadSize/1000));
      fPave->AddText(Form("Readextra = %5.2f per cent",extra));
      fPave->AddText(Form("Real Time = %7.3f s",fRealTime));
      fPave->AddText(Form("CPU  Time = %7.3f s",fCpuTime));
      fPave->AddText(Form("Disk Time = %7.3f s",fDiskTime));
      if (unzip) {
         fPave->AddText(Form("UnzipTime = %7.3f s",fUnzipTime));
      }
      fPave->AddText(Form("Disk IO   = %7.3f MB/s",1e-6*fBytesRead/fDiskTime));
      fPave->AddText(Form("ReadUZRT  = %7.3f MB/s",1e-6*fCompress*fBytesRead/fRealTime));
      fPave->AddText(Form("ReadUZCP  = %7.3f MB/s",1e-6*fCompress*fBytesRead/fCpuTime));
      fPave->AddText(Form("ReadRT    = %7.3f MB/s",1e-6*fBytesRead/fRealTime));
      fPave->AddText(Form("ReadCP    = %7.3f MB/s",1e-6*fBytesRead/fCpuTime));
   }
   fPave->Paint();

   if (!fHostInfoText) {
      fHostInfoText = new TText(0.01,0.01,fHostInfo.Data());
      fHostInfoText->SetNDC();
      fHostInfoText->SetTextSize(0.025);
   }
   fHostInfoText->Paint();
}

////////////////////////////////////////////////////////////////////////////////
/// Print the TTree I/O perf stats.

void TTreePerfStats::Print(Option_t * option) const
{
   TString opts(option);
   opts.ToLower();
   Bool_t unzip = opts.Contains("unzip");
   TTreePerfStats *ps = (TTreePerfStats*)this;
   ps->Finish();

   Double_t extra = 100.*fBytesReadExtra/fBytesRead;
   printf("TreeCache = %d MBytes\n",Int_t(fTreeCacheSize/1000000));
   printf("N leaves  = %d\n",fNleaves);
   printf("ReadTotal = %g MBytes\n",1e-6*fBytesRead);
   printf("ReadUnZip = %g MBytes\n",1e-6*fBytesRead*fCompress);
   printf("ReadCalls = %d\n",fReadCalls);
   printf("ReadSize  = %7.3f KBytes/read\n",0.001*fBytesRead/fReadCalls);
   printf("Readahead = %d KBytes\n",fReadaheadSize/1000);
   printf("Readextra = %5.2f per cent\n",extra);
   printf("Real Time = %7.3f seconds\n",fRealTime);
   printf("CPU  Time = %7.3f seconds\n",fCpuTime);
   printf("Disk Time = %7.3f seconds\n",fDiskTime);
   if (unzip) {
      printf("Strm Time = %7.3f seconds\n",fCpuTime-fUnzipTime);
      printf("UnzipTime = %7.3f seconds\n",fUnzipTime);
   }
   printf("Disk IO   = %7.3f MBytes/s\n",1e-6*fBytesRead/fDiskTime);
   printf("ReadUZRT  = %7.3f MBytes/s\n",1e-6*fCompress*fBytesRead/fRealTime);
   printf("ReadUZCP  = %7.3f MBytes/s\n",1e-6*fCompress*fBytesRead/fCpuTime);
   printf("ReadRT    = %7.3f MBytes/s\n",1e-6*fBytesRead/fRealTime);
   printf("ReadCP    = %7.3f MBytes/s\n",1e-6*fBytesRead/fCpuTime);
   if (unzip) {
      printf("ReadStrCP = %7.3f MBytes/s\n",1e-6*fCompress*fBytesRead/(fCpuTime-fUnzipTime));
      printf("ReadZipCP = %7.3f MBytes/s\n",1e-6*fCompress*fBytesRead/fUnzipTime);
   }
}

////////////////////////////////////////////////////////////////////////////////
/// Save this object to filename

void TTreePerfStats::SaveAs(const char *filename, Option_t * /*option*/) const
{
   TTreePerfStats *ps = (TTreePerfStats*)this;
   ps->Finish();
   ps->TObject::SaveAs(filename);
}

////////////////////////////////////////////////////////////////////////////////
/// Save primitive as a C++ statement(s) on output stream out

void TTreePerfStats::SavePrimitive(std::ostream &out, Option_t *option /*= ""*/)
{
   char quote = '"';
   out<<"   "<<std::endl;
   if (gROOT->ClassSaved(TTreePerfStats::Class())) {
      out<<"   ";
   } else {
      out<<"   TTreePerfStats *";
   }
   out<<"ps = new TTreePerfStats();"<<std::endl;
   out<<"   ps->SetName("<<quote<<GetName()<<quote<<");"<<std::endl;
   out<<"   ps->SetHostInfo("<<quote<<GetHostInfo()<<quote<<");"<<std::endl;
   out<<"   ps->SetTreeCacheSize("<<fTreeCacheSize<<");"<<std::endl;
   out<<"   ps->SetNleaves("<<fNleaves<<");"<<std::endl;
   out<<"   ps->SetReadCalls("<<fReadCalls<<");"<<std::endl;
   out<<"   ps->SetReadaheadSize("<<fReadaheadSize<<");"<<std::endl;
   out<<"   ps->SetBytesRead("<<fBytesRead<<");"<<std::endl;
   out<<"   ps->SetBytesReadExtra("<<fBytesReadExtra<<");"<<std::endl;
   out<<"   ps->SetRealNorm("<<fRealNorm<<");"<<std::endl;
   out<<"   ps->SetRealTime("<<fRealTime<<");"<<std::endl;
   out<<"   ps->SetCpuTime("<<fCpuTime<<");"<<std::endl;
   out<<"   ps->SetDiskTime("<<fDiskTime<<");"<<std::endl;
   out<<"   ps->SetUnzipTime("<<fUnzipTime<<");"<<std::endl;
   out<<"   ps->SetCompress("<<fCompress<<");"<<std::endl;

   Int_t i, npoints = fGraphIO->GetN();
   out<<"   TGraphErrors *psGraphIO = new TGraphErrors("<<npoints<<");"<<std::endl;
   out<<"   psGraphIO->SetName("<<quote<<fGraphIO->GetName()<<quote<<");"<<std::endl;
   out<<"   psGraphIO->SetTitle("<<quote<<fGraphIO->GetTitle()<<quote<<");"<<std::endl;
   out<<"   ps->SetGraphIO(psGraphIO);"<<std::endl;
   fGraphIO->SaveFillAttributes(out,"psGraphIO",0,1001);
   fGraphIO->SaveLineAttributes(out,"psGraphIO",1,1,1);
   fGraphIO->SaveMarkerAttributes(out,"psGraphIO",1,1,1);
   for (i=0;i<npoints;i++) {
      out<<"   psGraphIO->SetPoint("<<i<<","<<fGraphIO->GetX()[i]<<","<<fGraphIO->GetY()[i]<<");"<<std::endl;
      out<<"   psGraphIO->SetPointError("<<i<<",0,"<<fGraphIO->GetEY()[i]<<");"<<std::endl;
   }
   npoints = fGraphTime->GetN();
   out<<"   TGraphErrors *psGraphTime = new TGraphErrors("<<npoints<<");"<<std::endl;
   out<<"   psGraphTime->SetName("<<quote<<fGraphTime->GetName()<<quote<<");"<<std::endl;
   out<<"   psGraphTime->SetTitle("<<quote<<fGraphTime->GetTitle()<<quote<<");"<<std::endl;
   out<<"   ps->SetGraphTime(psGraphTime);"<<std::endl;
   fGraphTime->SaveFillAttributes(out,"psGraphTime",0,1001);
   fGraphTime->SaveLineAttributes(out,"psGraphTime",1,1,1);
   fGraphTime->SaveMarkerAttributes(out,"psGraphTime",1,1,1);
   for (i=0;i<npoints;i++) {
      out<<"   psGraphTime->SetPoint("<<i<<","<<fGraphTime->GetX()[i]<<","<<fGraphTime->GetY()[i]<<");"<<std::endl;
      out<<"   psGraphTime->SetPointError("<<i<<",0,"<<fGraphTime->GetEY()[i]<<");"<<std::endl;
   }

   out<<"   ps->Draw("<<quote<<option<<quote<<");"<<std::endl;
}