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Reference Guide
TTreeCacheUnzip.h
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1// Authors: Rene Brun 04/06/2006
2// Leandro Franco 10/04/2008
3// Fabrizio Furano (CERN) Aug 2009
4
5/*************************************************************************
6 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
7 * All rights reserved. *
8 * *
9 * For the licensing terms see $ROOTSYS/LICENSE. *
10 * For the list of contributors see $ROOTSYS/README/CREDITS. *
11 *************************************************************************/
12
13#ifndef ROOT_TTreeCacheUnzip
14#define ROOT_TTreeCacheUnzip
15
16#include "Bytes.h"
17#include "TTreeCache.h"
18#include <atomic>
19#include <memory>
20#include <vector>
21
22class TBasket;
23class TBranch;
24class TMutex;
25class TTree;
26
27#ifdef R__USE_IMT
28namespace ROOT {
29namespace Experimental {
30class TTaskGroup;
31}
32}
33#endif
34
36
37public:
38 // We have three possibilities for the unzipping mode:
39 // enable, disable and force
41
42 // Unzipping states for a basket:
44
45protected:
46 // Unzipping state for baskets
47 struct UnzipState {
48 // Note: we cannot use std::unique_ptr<std::unique_ptr<char[]>[]> or vector of unique_ptr
49 // for fUnzipChunks since std::unique_ptr is not copy constructable.
50 // However, in future upgrade we cannot use make_vector in C++14.
51 std::unique_ptr<char[]> *fUnzipChunks; ///<! [fNseek] Individual unzipped chunks. Their summed size is kept under control.
52 std::vector<Int_t> fUnzipLen; ///<! [fNseek] Length of the unzipped buffers
53 std::atomic<Byte_t> *fUnzipStatus; ///<! [fNSeek]
54
56 fUnzipChunks = nullptr;
57 fUnzipStatus = nullptr;
58 }
60 if (fUnzipChunks) delete [] fUnzipChunks;
61 if (fUnzipStatus) delete [] fUnzipStatus;
62 }
63 void Clear(Int_t size);
64 Bool_t IsUntouched(Int_t index) const;
65 Bool_t IsProgress(Int_t index) const;
66 Bool_t IsFinished(Int_t index) const;
67 Bool_t IsUnzipped(Int_t index) const;
68 void Reset(Int_t oldSize, Int_t newSize);
69 void SetUntouched(Int_t index);
70 void SetProgress(Int_t index);
71 void SetFinished(Int_t index);
72 void SetMissed(Int_t index);
73 void SetUnzipped(Int_t index, char* buf, Int_t len);
75 };
76
77 typedef struct UnzipState UnzipState_t;
79
80 // Members for paral. managing
84 Bool_t fParallel; ///< Indicate if we want to activate the parallelism (for this instance)
85
86 std::unique_ptr<TMutex> fIOMutex;
87
88 static TTreeCacheUnzip::EParUnzipMode fgParallel; ///< Indicate if we want to activate the parallelism
89
90 // IMT TTaskGroup Manager
91#ifdef R__USE_IMT
92 std::unique_ptr<ROOT::Experimental::TTaskGroup> fUnzipTaskGroup;
93#endif
94
95 // Unzipping related members
96 Int_t fNseekMax; ///<! fNseek can change so we need to know its max size
97 Int_t fUnzipGroupSize; ///<! Min accumulated size of a group of baskets ready to be unzipped by a IMT task
98 Long64_t fUnzipBufferSize; ///<! Max Size for the ready unzipped blocks (default is 2*fBufferSize)
99
100 static Double_t fgRelBuffSize; ///< This is the percentage of the TTreeCacheUnzip that will be used
101
102 // Members use to keep statistics
103 Int_t fNFound; ///<! number of blocks that were found in the cache
104 Int_t fNMissed; ///<! number of blocks that were not found in the cache and were unzipped
105 Int_t fNStalls; ///<! number of hits which caused a stall
106 Int_t fNUnzip; ///<! number of blocks that were unzipped
107
108private:
109 TTreeCacheUnzip(const TTreeCacheUnzip &); //this class cannot be copied
111
114
115 // Private methods
116 void Init();
117
118public:
120 TTreeCacheUnzip(TTree *tree, Int_t buffersize=0);
121 virtual ~TTreeCacheUnzip();
122
123 virtual Int_t AddBranch(TBranch *b, Bool_t subbranches = kFALSE);
124 virtual Int_t AddBranch(const char *branch, Bool_t subbranches = kFALSE);
126 virtual Int_t ReadBufferExt(char *buf, Long64_t pos, Int_t len, Int_t &loc);
127 void SetEntryRange(Long64_t emin, Long64_t emax);
128 virtual void StopLearningPhase();
130
131 // Methods related to the thread
133 static Bool_t IsParallelUnzip();
135
136 // Unzipping related methods
137#ifdef R__USE_IMT
139#endif
140 Int_t GetRecordHeader(char *buf, Int_t maxbytes, Int_t &nbytes, Int_t &objlen, Int_t &keylen);
141 virtual Int_t GetUnzipBuffer(char **buf, Long64_t pos, Int_t len, Bool_t *free);
143 virtual void ResetCache();
144 virtual Int_t SetBufferSize(Int_t buffersize);
145 void SetUnzipBufferSize(Long64_t bufferSize);
146 void SetUnzipGroupSize(Int_t groupSize) { fUnzipGroupSize = groupSize; }
147 static void SetUnzipRelBufferSize(Float_t relbufferSize);
148 Int_t UnzipBuffer(char **dest, char *src);
149 Int_t UnzipCache(Int_t index);
150
151 // Methods to get stats
152 Int_t GetNUnzip() { return fNUnzip; }
154 Int_t GetNFound() { return fNFound; }
155
156 void Print(Option_t* option = "") const;
157
158 // static members
159 ClassDef(TTreeCacheUnzip,0) //Specialization of TTreeCache for parallel unzipping
160};
161
162#endif
#define b(i)
Definition: RSha256.hxx:100
int Int_t
Definition: RtypesCore.h:41
const Bool_t kFALSE
Definition: RtypesCore.h:88
bool Bool_t
Definition: RtypesCore.h:59
double Double_t
Definition: RtypesCore.h:55
long long Long64_t
Definition: RtypesCore.h:69
float Float_t
Definition: RtypesCore.h:53
const char Option_t
Definition: RtypesCore.h:62
#define ClassDef(name, id)
Definition: Rtypes.h:326
#define free
Definition: civetweb.c:1539
Manages buffers for branches of a Tree.
Definition: TBasket.h:34
A TTree is a list of TBranches.
Definition: TBranch.h:91
Definition: TMutex.h:30
A TTreeCache which exploits parallelized decompression of its own content.
virtual void StopLearningPhase()
It's the same as TTreeCache::StopLearningPhase but we guarantee that we start the unzipping just afte...
UnzipState_t fUnzipState
Bool_t FillBuffer()
Fill the cache buffer with the branches in the cache.
void SetUnzipGroupSize(Int_t groupSize)
void Init()
Initialization procedure common to all the constructors.
Int_t UnzipCache(Int_t index)
This inflates a basket in the cache.
Int_t fNMissed
! number of blocks that were not found in the cache and were unzipped
Int_t GetUnzipGroupSize()
void SetEntryRange(Long64_t emin, Long64_t emax)
Set the minimum and maximum entry number to be processed this information helps to optimize the numbe...
TTreeCacheUnzip(const TTreeCacheUnzip &)
virtual Int_t ReadBufferExt(char *buf, Long64_t pos, Int_t len, Int_t &loc)
Int_t fNseekMax
! fNseek can change so we need to know its max size
virtual ~TTreeCacheUnzip()
Destructor. (in general called by the TFile destructor)
void UpdateBranches(TTree *tree)
update pointer to current Tree and recompute pointers to the branches in the cache
Int_t fNStalls
! number of hits which caused a stall
static TTreeCacheUnzip::EParUnzipMode fgParallel
Indicate if we want to activate the parallelism.
std::unique_ptr< ROOT::Experimental::TTaskGroup > fUnzipTaskGroup
static Int_t SetParallelUnzip(TTreeCacheUnzip::EParUnzipMode option=TTreeCacheUnzip::kEnable)
Static function that (de)activates multithreading unzipping.
Int_t UnzipBuffer(char **dest, char *src)
Unzips a ROOT specific buffer... by reading the header at the beginning.
Int_t GetRecordHeader(char *buf, Int_t maxbytes, Int_t &nbytes, Int_t &objlen, Int_t &keylen)
Read the logical record header from the buffer buf.
static void SetUnzipRelBufferSize(Float_t relbufferSize)
static function: Sets the unzip relatibe buffer size
void Print(Option_t *option="") const
Print cache statistics.
std::unique_ptr< TMutex > fIOMutex
Int_t fNUnzip
! number of blocks that were unzipped
Int_t CreateTasks()
We create a TTaskGroup and asynchronously maps each group of baskets(> 100 kB in total) to a task.
Bool_t fParallel
Indicate if we want to activate the parallelism (for this instance)
Long64_t fUnzipBufferSize
! Max Size for the ready unzipped blocks (default is 2*fBufferSize)
static Bool_t IsParallelUnzip()
Static function that tells wether the multithreading unzipping is activated.
void SetUnzipBufferSize(Long64_t bufferSize)
Sets the size for the unzipping cache... by default it should be two times the size of the prefetchin...
Int_t fUnzipGroupSize
! Min accumulated size of a group of baskets ready to be unzipped by a IMT task
virtual Int_t SetBufferSize(Int_t buffersize)
Change the underlying buffer size of the cache.
Int_t fNFound
! number of blocks that were found in the cache
virtual Int_t GetUnzipBuffer(char **buf, Long64_t pos, Int_t len, Bool_t *free)
We try to read a buffer that has already been unzipped Returns -1 in case of read failure,...
virtual Int_t AddBranch(TBranch *b, Bool_t subbranches=kFALSE)
Add a branch to the list of branches to be stored in the cache this function is called by TBranch::Ge...
static Double_t fgRelBuffSize
This is the percentage of the TTreeCacheUnzip that will be used.
virtual void ResetCache()
This will delete the list of buffers that are in the unzipping cache and will reset certain values in...
static EParUnzipMode GetParallelUnzip()
Static function that returns the parallel option (to indicate an additional thread)
TTreeCacheUnzip & operator=(const TTreeCacheUnzip &)
A cache to speed-up the reading of ROOT datasets.
Definition: TTreeCache.h:35
A TTree represents a columnar dataset.
Definition: TTree.h:72
VSD Structures.
Definition: StringConv.hxx:21
Definition: tree.py:1
Bool_t IsFinished(Int_t index) const
void Reset(Int_t oldSize, Int_t newSize)
Reset all baskets' state arrays.
void Clear(Int_t size)
Clear all baskets' state arrays.
Bool_t IsProgress(Int_t index) const
std::atomic< Byte_t > * fUnzipStatus
! [fNSeek]
void SetUnzipped(Int_t index, char *buf, Int_t len)
std::vector< Int_t > fUnzipLen
! [fNseek] Length of the unzipped buffers
Bool_t TryUnzipping(Int_t index)
Start unzipping the basket if it is untouched yet.
void SetProgress(Int_t index)
void SetUntouched(Int_t index)
Bool_t IsUnzipped(Int_t index) const
Check if the basket is unzipped already.
Bool_t IsUntouched(Int_t index) const
void SetFinished(Int_t index)
Set cache as finished.
std::unique_ptr< char[]> * fUnzipChunks
! [fNseek] Individual unzipped chunks. Their summed size is kept under control.
#define dest(otri, vertexptr)
Definition: triangle.c:1040