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DbiCache Class Reference

Concept Cache holding DbiResults for a specific database table. Purpose A DbiCache is an object that minimises database I/O by caching query results. Queries are always first sent to the cache and only if not present are they sent down to the database. More...

#include <DbiCache.h>

List of all members.

Public Types

typedef std::list< DbiResult * > ResultList_t

Public Member Functions

 DbiCache (DbiTableProxy &qp, const string &tableName)
virtual ~DbiCache ()
UInt_t GetMaxSize () const
UInt_t GetCurSize () const
UInt_t GetNumAdopted () const
UInt_t GetNumReused () const
const DbiResult * Search (const VldContext &vc, const Dbi::Task &task) const
 Primary searches.
const DbiResult * Search (const string &sqlQualifiers) const
const DbiResult * Search (const DbiValidityRec &vr, const string &sqlQualifiers="") const
 Secondary search.
MsgStream & ShowStatistics (MsgStream &msg) const
void Adopt (DbiResult *res, bool registerKey=true)
void Purge ()
void SetStale ()

Private Member Functions

 DbiCache (const DbiCache &)
DbiCache & operator= (const DbiCache &)
const ResultList_t * GetSubCache (Int_t aggNo) const
void Purge (ResultList_t &subCache, const DbiResult *res=0)

Private Attributes

DbiTableProxy & fTableProxy
 TableProxy owning cache.
const string & fTableName
 Name of associated table.
std::map< Int_t, ResultList_t > fCache
UInt_t fCurSize
 Current size.
UInt_t fMaxSize
 Max (high water) size.
UInt_t fNumAdopted
 Total number adopted.
UInt_t fNumReused
 Number reused i.e. found.

Friends

class DbiValidate

Detailed Description

Concept Cache holding DbiResults for a specific database table. Purpose A DbiCache is an object that minimises database I/O by caching query results. Queries are always first sent to the cache and only if not present are they sent down to the database.

Id
DbiCache.h,v 1.19 2006/08/08 10:51:32 west Exp

DatabaseInterface

Contact: n.west1@physics.ox.ac.uk

Definition at line 39 of file DbiCache.h.

Member Typedef Documentation

typedef std::list<DbiResult*> DbiCache::ResultList_t
 

Definition at line 47 of file DbiCache.h.

Referenced by Adopt(), Search(), SetStale(), and ~DbiCache().

Constructor & Destructor Documentation

DbiCache::DbiCache (  DbiTableProxy &  qp,
const string &  tableName
) 
 

Definition at line 39 of file DbiCache.cxx.

References LEA_CTOR, and MSG.

00039                                                             :
00040 fTableProxy(qp),
00041 fTableName(tableName),
00042 fCurSize(0),
00043 fMaxSize(0),
00044 fNumAdopted(0),
00045 fNumReused(0)
00046 {
00047 //
00048 //
00049 //  Purpose:  Constructor
00050 //
00051 //  Arguments:   
00052 //             in  qp         Owning DbiTableProxy.
00053 //             in  tableName  Name of associated table
00054 //
00055 //  Return:    n/a
00056 //
00057 //  Contact:   N. West
00058 //
00059 //  Specification:-
00060 //  =============
00061 //
00062 //  o Create empty cache.
00063 
00064 
00065 //  Program Notes:-
00066 //  =============
00067 
00068 //  None.
00069 
00070   LEA_CTOR    //Leak Checker
00071 
00072   MSG("Dbi", Msg::kVerbose) << "Creating DbiCache" << endl;
00073 
00074 }

DbiCache::~DbiCache (   )  [virtual]
 

Definition at line 78 of file DbiCache.cxx.

References CacheItr_t, fCache, GetSubCache(), LEA_DTOR, MSG, Purge(), ResultList_t, and SubCacheItr_t.

00078                     {
00079 //
00080 //
00081 //  Purpose: Destructor
00082 //
00083 //  Arguments: 
00084 //    None.
00085 //
00086 //  Return:    n/a
00087 //
00088 //  Contact:   N. West
00089 //
00090 //  Specification:-
00091 //  =============
00092 //
00093 //  o  Destroy cache and all owned DbiResults.
00094 
00095 
00096 //  Program Notes:-
00097 //  =============
00098 
00099 //  None.
00100 
00101   LEA_DTOR    //Leak Checker
00102 
00103   MSG("Dbi", Msg::kVerbose) << "Destroying DbiCache" << endl;
00104 
00105   // Purge the AggNo == -1 cache before deleting.  For extended
00106   // context queries it can have DbiResultAggs that are clients of 
00107   // DbiResultNonAggs in the same cache, so purging will remove clientless
00108   // DbiResultAggs which should in turn make their DbiResultNonAggs 
00109   // clientless.
00110   if ( this->GetSubCache(-1) ) this->Purge(fCache[-1]);
00111 
00112   for ( CacheItr_t itr = fCache.begin(); itr != fCache.end(); ++itr) {
00113     ResultList_t& subCache = itr->second;
00114     for ( SubCacheItr_t sitr = subCache.begin();
00115           sitr != subCache.end();
00116           ++sitr) delete *sitr;
00117   }
00118 
00119 }

DbiCache::DbiCache (  const DbiCache &   )  [private]
 

Member Function Documentation

void DbiCache::Adopt (  DbiResult *  res,
bool  registerKey = true
) 
 

Definition at line 123 of file DbiCache.cxx.

References fCache, fCurSize, fMaxSize, DbiValidityRec::GetAggregateNo(), DbiResult::GetKey(), GetSubCache(), DbiResult::GetValidityRec(), DbiResult::GetValidityRecGlobal(), MSG, Purge(), DbiResult::RegisterKey(), ResultList_t, and DbiResult::TableName().

Referenced by DbiTableProxy::Query(), and DbiTableProxy::RestoreFromL2Cache().

00123                                                     {
00124 //
00125 //
00126 //  Purpose:  Adopt and own a DbiResult
00127 //
00128 //  Arguments: 
00129 //    res          in    The DbiResiult to be adopted.
00130 //    registerKey  in    If true, register key with DbiRecord.
00131 //
00132 //  Return:  None.
00133 //
00134 //  Contact:   N. West
00135 //
00136 //  Specification:-
00137 //  =============
00138 //
00139 //  o Create new sub-cache for aggregate if necessary.
00140 //
00141 //  o Purge sub-cache of unwanted data and adopt new result.
00142 
00143 //  Program Notes:-
00144 //  =============
00145 
00146 //  New entries are added to the end of the sub-cache unwanted entries
00147 //  are always removed from the beginning so sub-cache is a FIFO.
00148 
00149   if ( ! res ) return;
00150   int aggNo = res->GetValidityRec().GetAggregateNo();
00151 
00152 //  Prime sub-cache if necessary.
00153   if ( ! this->GetSubCache(aggNo) ) {
00154     ResultList_t emptyList;
00155     fCache[aggNo] = emptyList;
00156   }
00157 
00158 //  Purge expired entries and add new result to cache.
00159   ResultList_t& subCache = fCache[aggNo];
00160   Purge(subCache, res);
00161   subCache.push_back(res);
00162   ++fCurSize;
00163   ++fNumAdopted;
00164   MSG("Dbi",Msg::kDebug) << "Adopting result for " << res->TableName()
00165                          << "  " <<   res->GetValidityRecGlobal() 
00166                          << "\nCache size now " << fCurSize << endl;
00167   if ( fCurSize > fMaxSize ) fMaxSize = fCurSize;
00168   // If required register key with DbiRecord
00169   if ( registerKey ) {
00170     res->RegisterKey();
00171     MSG("Dbi",Msg::kInfo) << "Caching new results: ResultKey: " <<  *res->GetKey();
00172   }
00173 }

UInt_t DbiCache::GetCurSize (   )  const [inline]
 

Definition at line 58 of file DbiCache.h.

00058 { return fCurSize; }

UInt_t DbiCache::GetMaxSize (   )  const [inline]
 

Definition at line 57 of file DbiCache.h.

00057 { return fMaxSize; }

UInt_t DbiCache::GetNumAdopted (   )  const [inline]
 

Definition at line 59 of file DbiCache.h.

00059 { return fNumAdopted; }

UInt_t DbiCache::GetNumReused (   )  const [inline]
 

Definition at line 60 of file DbiCache.h.

00060 { return fNumReused; }

const ResultList_t * DbiCache::GetSubCache (  Int_t  aggNo  )  const [private]
 

Definition at line 177 of file DbiCache.cxx.

References ConstCacheItr_t, fCache, and ResultList_t.

Referenced by Adopt(), Search(), and ~DbiCache().

00177                                                            {
00178 //
00179 //
00180 //  Purpose:  Return sub-cache for aggregate or 0 if none..
00181 
00182   ConstCacheItr_t itr = fCache.find(aggNo);
00183   return ( itr == fCache.end() ) ? 0 : &itr->second;
00184 
00185 }

DbiCache& DbiCache::operator= (  const DbiCache &   )  [private]
 

void DbiCache::Purge (  ResultList_t &  subCache,
const DbiResult *  res = 0
)  [private]
 

Definition at line 220 of file DbiCache.cxx.

References DbiResult::CanDelete(), fCurSize, DbiResult::GetNumClients(), DbiResult::GetValidityRec(), MSG, SubCacheItr_t, and DbiResult::TableName().

00220                                                                  {
00221 //
00222 //
00223 //  Purpose: Purge surplus sub-cache memebers. 
00224 //
00225 //  Arguments:
00226 //    subCache   in/out  The sub-cache to be purged
00227 //    res        in      Optional DbiResult (default =0)
00228 //
00229 //  Return:   None. 
00230 //
00231 //  Contact:   N. West
00232 //
00233 //  Specification:-
00234 //  =============
00235 //
00236 //  o Purge surplus sub-cache members i.e. those without clients.
00237 //
00238 //  o If a DbiResult is supplied, only purge entries that have
00239 //    expired relative to it or are stale.
00240 
00241 //  Program Notes:-
00242 //  =============
00243 
00244 //  Passing a DbiResult allows the sub-cache to hold entries
00245 //  for different detector types, simulation masks and tasks.
00246 
00247     for ( SubCacheItr_t itr = subCache.begin(); itr != subCache.end(); ) {
00248     DbiResult* pRes = *itr;
00249 
00250      if (      pRes->GetNumClients() == 0 
00251           && (    ! res 
00252                || pRes->CanDelete(res)  ) ) {
00253 
00254       MSG("Dbi",Msg::kDebug) << "Purging " << pRes->GetValidityRec()
00255                              << " from " << pRes->TableName() 
00256                              << " cache. Cache size now " 
00257                              << fCurSize-1 << endl;
00258       delete pRes;
00259 //    Erasing increments iterator.
00260       itr = subCache.erase(itr);
00261       --fCurSize;
00262 
00263     }
00264     else {
00265       ++itr;
00266     }
00267   }
00268 
00269 }

void DbiCache::Purge (   ) 
 

Definition at line 189 of file DbiCache.cxx.

References CacheItr_t, and fCache.

Referenced by Adopt(), Plexus::BuildLedMaps(), Plexus::BuildPinDiodeMap(), Plexus::BuildPixelMaps(), Plexus::BuildReadoutMap(), UgliGeometry::ClearDbiCache(), DTFtest(), DbiTableProxyRegistry::PurgeCaches(), and ~DbiCache().

00189                      {
00190 //
00191 //
00192 //  Purpose: Purge all sub-caches. 
00193 //
00194 //  Arguments:  None.
00195 //
00196 //  Return:   None. 
00197 //
00198 //  Contact:   N. West
00199 //
00200 //  Specification:-
00201 //  =============
00202 //
00203 //  o Purge all sub_caches.
00204 
00205 //  Program Notes:-
00206 //  =============
00207 
00208 //  The first sub-cached to be purged must be sub-cache -1 as
00209 //  its members may be aggregated and consequently will be
00210 //  connected to members in other caches.
00211 
00212 
00213 
00214   for ( CacheItr_t itr = fCache.begin(); itr != fCache.end(); ++itr
00215       ) Purge(itr->second);
00216 
00217 }

const DbiResult * DbiCache::Search (  const DbiValidityRec &  vr,
const string &  sqlQualifiers = ""
)  const
 

Secondary search.

Definition at line 272 of file DbiCache.cxx.

References ConstSubCacheItr_t, fNumReused, fTableName, DbiValidityRec::GetAggregateNo(), DbiResult::GetNumAggregates(), DbiResult::GetNumRows(), GetSubCache(), MSG, ResultList_t, and DbiResult::Satisfies().

00273                                                                      {
00274 //
00275 //
00276 //  Purpose:  Search sub-cache for DbiResult set matching a DbiValidityRec. 
00277 //            with an optional sqlQualifiers string.
00278 //  Return:   Pointer to matching DbiResult, or = 0 if none. 
00279 
00280 
00281   Int_t aggNo = vrec.GetAggregateNo();
00282 
00283   MSG("Dbi",Msg::kSynopsis) << "Secondary cache search of table " << fTableName
00284                          << " for  " << vrec
00285                             << (sqlQualifiers != "" ? sqlQualifiers : "" ) << endl;
00286   const ResultList_t* subCache = this->GetSubCache(aggNo);
00287   if ( ! subCache ) {
00288     MSG("Dbi",Msg::kSynopsis) << "Secondary cache search failed." << endl;
00289     return 0;
00290   }
00291 
00292   ConstSubCacheItr_t itrEnd = subCache->end();
00293   for ( ConstSubCacheItr_t itr = subCache->begin();
00294         itr != itrEnd;
00295         ++itr) {
00296     DbiResult* res = *itr;
00297     if ( res->Satisfies(vrec,sqlQualifiers) ) {
00298       fNumReused += res->GetNumAggregates();
00299       MSG("Dbi",Msg::kSynopsis) << "Secondary cache search succeeded.  Result set no. of rows: " 
00300                                 << res->GetNumRows() << endl;
00301       return res;
00302     }
00303   }
00304 
00305   MSG("Dbi",Msg::kSynopsis) << "Secondary cache search failed." << endl;
00306   return 0;
00307 }

const DbiResult * DbiCache::Search (  const string &  sqlQualifiers  )  const
 

Definition at line 370 of file DbiCache.cxx.

References ConstSubCacheItr_t, fNumReused, fTableName, DbiResult::GetNumAggregates(), DbiResult::GetNumRows(), GetSubCache(), MSG, ResultList_t, and DbiResult::Satisfies().

00370                                                                    {
00371 //
00372 //
00373 //  Purpose:  Search primary cache for DbiResult set matching a new query. 
00374 //
00375 //  Arguments: 
00376 //    sqlQualifiers  in  The SQL qualifiers (context-sql;data-sql;fill-options)
00377 //
00378 //  Return:   Pointer to matching DbiResult, or = 0 if none. 
00379 
00380   MSG("Dbi",Msg::kSynopsis) << "Primary cache search of table " << fTableName
00381                          << " for  SQL " << sqlQualifiers << endl;
00382   const ResultList_t* subCache = this->GetSubCache(-1);
00383   if ( ! subCache ) {
00384     MSG("Dbi",Msg::kSynopsis) << "Primary cache search failed" << endl;
00385     return 0;
00386   }
00387   for ( ConstSubCacheItr_t itr = subCache->begin();
00388         itr != subCache->end();
00389         ++itr) {
00390     DbiResult* res = *itr;
00391     if ( res->Satisfies(sqlQualifiers) ) {
00392       fNumReused += res->GetNumAggregates();
00393       MSG("Dbi",Msg::kSynopsis) << "Primary cache search succeeded Result set no. of rows: " 
00394                                 << res->GetNumRows() << endl;
00395       return res;
00396     }
00397   }
00398   MSG("Dbi",Msg::kSynopsis) << "Primary cache search failed" << endl;
00399   return 0;
00400 }

const DbiResult * DbiCache::Search (  const VldContext &  vc,
const Dbi::Task &  task
)  const
 

Primary searches.

Definition at line 311 of file DbiCache.cxx.

References SimFlag::AsString(), ConstSubCacheItr_t, det, fNumReused, fTableName, DbiSimFlagAssociation::Get(), VldContext::GetDetector(), DbiResult::GetNumAggregates(), DbiResult::GetNumRows(), VldContext::GetSimFlag(), GetSubCache(), VldContext::GetTimeStamp(), DbiSimFlagAssociation::Instance(), MSG, ResultList_t, DbiResult::Satisfies(), and DbiSimFlagAssociation::SimList_t.

Referenced by DbiTableProxy::Query(), and DbiTableProxy::RestoreFromL2Cache().

00312                                                               {
00313 //
00314 //
00315 //  Purpose:  Search primary cache for DbiResult set matching a new query. 
00316 //
00317 //  Arguments: 
00318 //    vc           in    Context of new query
00319 //    task         in    Task of new query
00320 //
00321 //  Return:   Pointer to matching DbiResult, or = 0 if none. 
00322 
00323   MSG("Dbi",Msg::kSynopsis) << "Primary cache search of table " << fTableName
00324                          << " for  " << vc
00325                          << " with task " << task << endl;
00326   const ResultList_t* subCache = this->GetSubCache(-1);
00327   if ( ! subCache ) {
00328     MSG("Dbi",Msg::kSynopsis) << "Primary cache search failed - sub-cache -1 is empty" << endl;
00329     return 0;
00330   }
00331 
00332   // Loop over all possible SimFlag associations.
00333 
00334   Detector::Detector_t     det(vc.GetDetector());
00335   SimFlag::SimFlag_t       sim(vc.GetSimFlag());
00336   VldTimeStamp              ts(vc.GetTimeStamp());
00337 
00338   DbiSimFlagAssociation::SimList_t simList 
00339                   = DbiSimFlagAssociation::Instance().Get(sim);
00340 
00341   DbiSimFlagAssociation::SimList_t::iterator listItr    = simList.begin();
00342   DbiSimFlagAssociation::SimList_t::iterator listItrEnd = simList.end();
00343   while ( listItr !=  listItrEnd ) {
00344 
00345     SimFlag::SimFlag_t simTry = *listItr;
00346     VldContext vcTry(det,simTry,ts);
00347 
00348     MSG("Dbi",Msg::kDebug) << "  Searching cache with SimFlag: "
00349                            << SimFlag::AsString(simTry) << endl;
00350     for ( ConstSubCacheItr_t itr = subCache->begin();
00351           itr != subCache->end();
00352           ++itr) {
00353       DbiResult* res = *itr;
00354       if ( res->Satisfies(vcTry,task) ) {
00355         fNumReused += res->GetNumAggregates();
00356         MSG("Dbi",Msg::kSynopsis) << "Primary cache search succeeded. Result set no. of rows: " 
00357                                   << res->GetNumRows() << endl; 
00358         return res;
00359       }
00360     }
00361 
00362   MSG("Dbi",Msg::kSynopsis) << "Primary cache search failed." << endl;
00363   ++listItr;
00364   }
00365 
00366   return 0;
00367 }

void DbiCache::SetStale (   ) 
 

Definition at line 404 of file DbiCache.cxx.

References CacheItr_t, fCache, ResultList_t, DbiResult::SetCanReuse(), and SubCacheItr_t.

Referenced by PulserDBModule::DeleteGC(), PulserDBModule::DoWriteGC(), UgliGeometryReroot::MakeTempDbiGeometry(), UgliGeometryReroot::MakeTempDbiPosInfo(), and UgliGeometryReroot::MakeTempDbiScintStruct().

00404                         {
00405 //
00406 //
00407 //  Purpose: Set all entries in the cache as stale i.e. don't reuse. 
00408 //
00409 //  Arguments: None
00410 //
00411 //  Return:    n/a
00412 //
00413 //  Contact:   N. West
00414 //
00415 //  Specification:-
00416 //  =============
00417 //
00418 //  o Set all entries in the cache as stale i.e. don't reuse. 
00419 
00420 //  Program Notes:-
00421 //  =============
00422 
00423 //  This member function can be used to effectively clear the cache.
00424 //  As existing DbiResult objects currently in the cache may currently
00425 //  have clients, its not possible simply to delete them, so instead
00426 //  this function marks them as stale so they will not be reused and
00427 //  will eventually be dropped once all their clients have disconnected.
00428 
00429 
00430   for ( CacheItr_t cacheItr = fCache.begin(); 
00431         cacheItr != fCache.end(); 
00432         ++cacheItr
00433         ) {
00434     ResultList_t& subcache = cacheItr->second;
00435 
00436     for ( SubCacheItr_t subcacheItr = subcache.begin(); 
00437           subcacheItr != subcache.end();
00438           ++subcacheItr ) (*subcacheItr)->SetCanReuse(kFALSE);
00439   }
00440 
00441 }

MsgStream & DbiCache::ShowStatistics (  MsgStream &  msg  )  const
 

Definition at line 445 of file DbiCache.cxx.

References fCurSize, fMaxSize, fNumAdopted, and fNumReused.

00445                                                         {
00446 //
00447 //
00448 //  Purpose: Display statistics for cache on supplied MsgStream.  
00449 //
00450 //  Arguments: 
00451 //    msg          in    MsgStream to output on.
00452 //
00453 //  Return: Updated MsgStream. 
00454 //
00455 //  Contact:   N. West
00456 //
00457 //  Specification:-
00458 //  =============
00459 //
00460 //  o Output : Current Size, Max size, Adopted and Resused as
00461 //             4 10 character wide fields.
00462 
00463 //  Program Notes:-
00464 //  =============
00465 
00466 //  None.
00467 
00468   MsgFormat ifmt("%10i");
00469 
00470   msg << ifmt(fCurSize) << ifmt(fMaxSize) 
00471       << ifmt(fNumAdopted) << ifmt(fNumReused);
00472   return msg;
00473 
00474 }

Friends And Related Function Documentation

friend class DbiValidate [friend]
 

Definition at line 42 of file DbiCache.h.

Member Data Documentation

std::map<Int_t,ResultList_t> DbiCache::fCache [private]
 

Map of sub-caches indexed by aggregate number. Each sub-cache is a list of owned results for that aggregate.

Definition at line 103 of file DbiCache.h.

Referenced by Adopt(), GetSubCache(), Purge(), SetStale(), and ~DbiCache().

UInt_t DbiCache::fCurSize [mutable, private]
 

Current size.

Definition at line 106 of file DbiCache.h.

Referenced by Adopt(), Purge(), and ShowStatistics().

UInt_t DbiCache::fMaxSize [mutable, private]
 

Max (high water) size.

Definition at line 109 of file DbiCache.h.

Referenced by Adopt(), and ShowStatistics().

UInt_t DbiCache::fNumAdopted [mutable, private]
 

Total number adopted.

Definition at line 112 of file DbiCache.h.

Referenced by ShowStatistics().

UInt_t DbiCache::fNumReused [mutable, private]
 

Number reused i.e. found.

Definition at line 115 of file DbiCache.h.

Referenced by Search(), and ShowStatistics().

const string& DbiCache::fTableName [private]
 

Name of associated table.

Definition at line 98 of file DbiCache.h.

Referenced by Search().

DbiTableProxy& DbiCache::fTableProxy [private]
 

TableProxy owning cache.

Definition at line 95 of file DbiCache.h.

The documentation for this class was generated from the following files:
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