src/server/csqlcheckpointserver.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 <AbsSqlConnection.h>
  17 #include <AbsSqlStatement.h>
  18 #include <SqlConnection.h>
  19 #include <SqlStatement.h>
  20 #include <SqlFactory.h>
  21 #include <CSql.h>
  22 #include <SessionImpl.h>
  23 #include <NanoTimer.h>
  24
  25 int srvStop =0;
  26 static void sigTermHandler(int sig)
  27 {
  28     printf("Received signal %d\nStopping the server\n", sig);
  29     srvStop = 1;
  30 }
  31 static void sigChildHandler(int sig)
  32 {
  33     os::signal(SIGCHLD, sigChildHandler);
  34     int stat;
  35     waitpid(-1, &stat, WNOHANG);
  36     //TODO::move waitpid to os wrapper
  37 }
  38
  39
  40 void printUsage()
  41 {
  42    printf("Usage: csqlcheckpointserver \n");
  43    printf("Description: Start the csql checkpoint server.\n");
  44    return;
  45 }
  46 DbRetVal takeCheckpoint()
  47 {
  48     char fileName[MAX_FILE_LEN];
  49     sprintf(fileName, "%s/csql.db.cur", Conf::config.getDbFile());
  50     if (::access(fileName, F_OK) != 0 ) return OK;
  51     int fileSize = os::getFileSize(fileName);
  52     logFine(Conf::logger, "Redo log file size %d", fileSize);
  53     if (fileSize < Conf::config.getChkptRedoLimit()) return  OK;
  54
  55     Connection conn;
  56     DbRetVal rv = conn.open(I_USER, I_PASS);
  57     if (rv != OK) return rv;
  58     DatabaseManager *dbMgr = conn.getDatabaseManager();
  59     NanoTimer timer;
  60     timer.reset();
  61     timer.start();
  62     int tries = 0, totalTries=10;
  63     while(tries < totalTries) {
  64        rv = dbMgr->checkPoint();
  65            if (rv == ErrLoadingOn) {
  66            conn.close();
  67            timer.stop();
  68            return rv;
  69        }
  70        if (rv == ErrLockTimeOut) {
  71           os::sleep(1); //sleep for 1 second
  72        } else if (rv != OK) {
  73           printError(rv, "checkpoint: failed");
  74           conn.close();
  75           timer.stop();
  76           return rv;
  77        }else  if (rv == OK) break;
  78        tries++;
  79     }
  80     timer.stop();
  81     if (rv != ErrLockTimeOut) {
  82         logFine(Conf::logger, "Checkpoint taken %lld microsecs", timer.avg()/1000);
  83         //printf("Time Taken for checkpoint %lld\n", timer.avg()/1000/1000);
  84     } else {
  85         logFine(Conf::logger, "Checkpoint:Could not get TXN consistent point");
  86     }
  87     conn.close();
  88     return OK;
  89 }
  90 int main(int argc, char **argv)
  91 {
  92     int c = 0, opt = 0;
  93     while ((c = getopt(argc, argv, "?")) != EOF)
  94     {
  95         switch (c)
  96         {
  97             case '?' : { opt = 10; break; } //print help
  98             default: opt=10;
  99
 100         }
 101     }//while options
 102
 103     if (opt == 10) {
 104         printUsage();
 105         return 0;
 106     }
 107     SessionImpl session;
 108     DbRetVal rv = session.readConfigFile();
 109     if (rv != OK)
 110     {
 111         printError(ErrSysInternal,"Unable to read the configuration file \n");
 112         return 1;
 113     }
 114     os::signal(SIGINT, sigTermHandler);
 115     os::signal(SIGTERM, sigTermHandler);
 116     os::signal(SIGCHLD, sigChildHandler);
 117
 118     if (!Conf::config.useDurability())
 119     {
 120         printError(ErrSysInternal, "Durablity is set to OFF in csql.conf file\n");
 121         return 1;
 122     }
 123     logFine(Conf::logger, "CSQL Checkpoint server started");
 124     int ret = 0;
 125     struct timeval timeout, tval;
 126     timeout.tv_sec = Conf::config.getChkptSecs();
 127     tval.tv_usec = 0;
 128
 129     while(!srvStop)
 130     {
 131         tval.tv_sec = timeout.tv_sec;
 132         ret = os::select(0, 0, 0, 0, &tval);
 133         if (srvStop) break;
 134         takeCheckpoint();
 135     }
 136     printf("Csql Checkpoint Daemon Exiting\n");
 137     logFine(Conf::logger, "CSQL Checkpoint server exiting");
 138     return 0;
 139 }