src/storage/TransactionManager.cxx

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by www.databasecache.com                           *
   3  *   Contact: praba_tuty@databasecache.com                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15   ***************************************************************************/
  16 #include<Transaction.h>
  17 #include<Lock.h>
  18 #include<Database.h>
  19 #include<Allocator.h>
  20 #include<CatalogTables.h>
  21 #include<Debug.h>
  22 #include<Config.h>
  23 #include<Process.h>
  24
  25 void TransactionManager::printUsageStatistics()
  26 {
  27     Transaction *iter = firstTrans;
  28     int i=0, usedCount =0, freeCount =0, undoLogCount=0;
  29     for (; i < Conf::config.getMaxProcs(); i++)
  30     {
  31             if (iter->status_ == TransNotUsed || iter->status_ == TransReserved) freeCount++;
  32             else
  33             {
  34                 usedCount++;
  35                 undoLogCount += iter->noOfUndoLogs();
  36             }
  37             iter++;
  38     }
  39     printf("<TransactionTable>\n");
  40     printf("  <UsedSlots> %d </UsedSlots>\n", usedCount);
  41     printf("  <FreeSlots> %d </FreeSlots>\n", freeCount);
  42
  43     printf("  <UndoLogs>\n");
  44     printf("    <TotalNodes> %d </TotalNodes>\n", undoLogCount);
  45     printf("  </UndoLogs>\n");
  46     printf("</TransactionTable>\n");
  47
  48 }
  49
  50 void TransactionManager::printDebugInfo(Database *sysdb)
  51 {
  52     Transaction *iter = firstTrans;
  53     int i=0, usedCount =0, freeCount =0, undoLogCount=0;
  54     printf("<TransactionTable>\n");
  55     for (; i < Conf::config.getMaxProcs(); i++)
  56     {
  57             if (iter->status_ == TransNotUsed || iter->status_ == TransReserved) freeCount++;
  58             else
  59             {
  60                 usedCount++;
  61                 undoLogCount += iter->noOfUndoLogs();
  62                 iter->printDebugInfo(sysdb);
  63             }
  64             iter++;
  65     }
  66
  67     printf("  <UsedSlots> %d </UsedSlots>\n", usedCount);
  68     printf("  <FreeSlots> %d </FreeSlots>\n", freeCount);
  69
  70     Chunk *chunk = sysdb->getSystemDatabaseChunk(UndoLogTableID);
  71
  72     printf("  <UndoLogs>\n");
  73     printf("    <TotalNodes> %d </TotalNodes>\n", undoLogCount);
  74     printf("    <TotalPages> %d </TotalPages>\n", chunk->totalPages());
  75     printf("  </UndoLogs>\n");
  76     printf("</TransactionTable>\n");
  77 }
  78
  79
  80 DbRetVal TransactionManager::startTransaction(LockManager *lMgr, IsolationLevel level)
  81 {
  82     Database *sysdb = lMgr->systemDatabase_;
  83     Transaction *trans = ProcessManager::getThreadTransaction(sysdb->procSlot);
  84     if (NULL != trans)
  85     {
  86         //
  87         if (trans->status_ != TransReserved) return ErrAlready;
  88         else if (trans->status_ == TransReserved)
  89         {
  90             //the previous transaction shall be used again
  91             //trans->status_ = TransRunning;
  92             if ( 0 != Mutex::CAS((int*)&trans->status_,
  93                                     TransReserved, TransRunning)) {
  94                 printError(ErrLockTimeOut, "unable to get lock to reuse the transaction");
  95                 return ErrLockTimeOut;
  96             }
  97             trans->isoLevel_ = level;
  98             printDebug(DM_Transaction, "Using the same transaction slot\n");
  99             logFinest(Conf::logger, "Transaction Start:Reusing :%x", trans);
 100             return OK;
 101         }
 102
 103     }
 104
 105     DbRetVal rv = sysdb->getTransTableMutex();
 106     if (OK != rv)
 107     {
 108         printError(rv, "Unable to acquire transtable mutex");
 109         return rv;
 110     }
 111     Transaction *iter = firstTrans;
 112     int i;
 113     for (i =0 ; i < Conf::config.getMaxProcs(); i++)
 114     {
 115             if (iter->status_ == TransNotUsed) break;
 116             iter++;
 117     }
 118     // if Transaction table is full return error
 119     if (i == Conf::config.getMaxProcs()) {
 120         printError(ErrNoResource, "Transaction slots are full");
 121         sysdb->releaseTransTableMutex();
 122         return ErrNoResource;
 123     }
 124     printDebug(DM_Transaction, "Using transaction slot %d \n", i);
 125
 126     //Make this free slot, as the current transaction and
 127     //set the state
 128     trans = iter;
 129     //trans->status_ = TransRunning;
 130     if ( 0 != Mutex::CAS((int*)&trans->status_ ,
 131                            TransNotUsed, TransRunning)) {
 132         printError(ErrLockTimeOut, "Unable to start transaction. Timeout. Retry..");
 133         sysdb->releaseTransTableMutex();
 134         return ErrLockTimeOut;
 135     }
 136     trans->isoLevel_ = level;
 137     ProcessManager::setThreadTransaction(trans, sysdb->procSlot);
 138     sysdb->releaseTransTableMutex();
 139     logFinest(Conf::logger, "Transaction Start:Using :%x", trans);
 140     return OK;
 141 }
 142
 143 void TransactionManager::setFirstTrans(Transaction *trans)
 144 {
 145     firstTrans = trans;
 146 }
 147
 148
 149 DbRetVal TransactionManager::commit(LockManager *lockManager)
 150 {
 151     Database *sysdb = lockManager->systemDatabase_;
 152     Transaction *trans = ProcessManager::getThreadTransaction(sysdb->procSlot);
 153     DbRetVal rv = OK;
 154     if (NULL == trans)
 155     {
 156        printError(ErrNotOpen, "No transaction started for this procSlot %d", sysdb->procSlot);
 157        return ErrNotOpen;
 158     }
 159     rv = trans->releaseAllLocks(lockManager);
 160     if (rv != OK) {
 161         printError(ErrSysInternal, "Fatal:Unable to release all the locks\n");
 162     }
 163     if(NULL != trans->waitLock_)
 164     {
 165         printError(ErrSysInternal, "Fatal:Trans WaitLock is not null\n");
 166     }
 167     trans->removeUndoLogs(sysdb);
 168     if ( 0 != Mutex::CAS((int*)&trans->status_, TransRunning, TransReserved))
 169     {
 170         printError(ErrSysFatal, "Transaction state corrupted %d\n", trans->status_);
 171         return ErrSysFatal;
 172     }
 173     printDebug(DM_Transaction, "Committed transaction:%x",trans);
 174     logFinest(Conf::logger, "Transaction Committed:%x", trans);
 175     return OK;
 176 }
 177
 178 DbRetVal TransactionManager::rollback(LockManager *lockManager, Transaction *t)
 179 {
 180     Database *sysdb = lockManager->systemDatabase_;
 181     Transaction *trans = NULL;
 182     DbRetVal rv = OK;
 183     if (t == NULL)
 184         trans = ProcessManager::getThreadTransaction(sysdb->procSlot);
 185     else
 186         trans = t;
 187     if (NULL == trans)
 188     {
 189        return OK;
 190     }
 191
 192     if (trans->status_ != TransRunning)
 193     {
 194         //sysdb->releaseTransTableMutex();
 195         //will be called during connection disconnect without starting transaction.
 196         return OK;
 197     }
 198
 199     trans->applyUndoLogs(sysdb);
 200     rv = trans->releaseAllLocks(lockManager);
 201     if (rv != OK) {
 202         printError(ErrSysInternal, "Fatal:Unable to release all the locks");
 203     }
 204     if(NULL != trans->waitLock_)
 205     {
 206         printError(ErrSysInternal, "Fatal:Trans waitlock is not null");
 207         //return ErrSysInternal;
 208     }
 209
 210     //trans->status_ = TransNotUsed;
 211     if ( 0 != Mutex::CAS((int*)&trans->status_, TransRunning, TransReserved))
 212     {
 213         printError(ErrSysFatal, "Fatal:Unable to abort transaction %d\n", trans->status_);
 214         return ErrSysFatal;
 215     }
 216     printDebug(DM_Transaction, "Aborted transaction:%x",trans);
 217     logFinest(Conf::logger, "Transaction Aborted:%x", trans);
 218     return OK;
 219 }
 220 bool TransactionManager::isTransactionConsistent(Database *sysdb)
 221 {
 222     DbRetVal rv = sysdb->getTransTableMutex();
 223     if (OK != rv)
 224     {
 225         printError(rv, "Unable to acquire transtable mutex");
 226         return false;
 227     }
 228     Transaction *iter = firstTrans;
 229     int i;
 230     for (i =0 ; i < Conf::config.getMaxProcs(); i++)
 231     {
 232         if (iter->status_ == TransRunning && iter->noOfUndoLogs()) {
 233             printError( ErrSysInternal, "Transaction slot %d not consistent status:%d undoLogs:%d\n",i, iter->status_, iter->noOfUndoLogs());
 234             sysdb->releaseTransTableMutex();
 235             return false;
 236         }
 237         iter++;
 238     }
 239     sysdb->releaseTransTableMutex();
 240     return true;
 241 }