@@ -52,6 +52,7 @@ struct config
5252int updatePercent;
5353int nShards;
5454 string connection;
55+ bool prepared;
5556
5657config () {
5758nShards =1 ;
@@ -60,6 +61,7 @@ struct config
6061 nIterations =1000 ;
6162 nAccounts =10000 ;
6263 updatePercent =100 ;
64+ prepared =false ;
6365 }
6466};
6567
@@ -76,14 +78,14 @@ static time_t getCurrentTime()
7678}
7779
7880
79- void exec (transaction_base& txn,char const * sql, ...)
81+ int exec (transaction_base& txn,char const * sql, ...)
8082{
8183 va_list args;
8284va_start (args, sql);
8385char buf[1024 ];
8486vsprintf (buf, sql, args);
8587va_end (args);
86- txn.exec (buf);
88+ return exec (buf). affected_rows ( );
8789}
8890
8991template <class T >
@@ -123,15 +125,28 @@ void* writer(void* arg)
123125{
124126 thread& t = *(thread*)arg;
125127 connectionconn (cfg.connection );
128+ if (cfg.prepared ) {
129+ conn.prepare (" transfer" " update t set v = v + $1 where u=$2"
130+ }
126131for (int i =0 ; i < cfg.nIterations ; i++)
127132 {
128133worktxn (conn);
129134int srcAcc =random () % cfg.nAccounts ;
130135int dstAcc =random () % cfg.nAccounts ;
131136try {
132- if (random () %100 < cfg.updatePercent ) {
133- exec (txn," update t set v = v - 1 where u=%d"
134- exec (txn," update t set v = v + 1 where u=%d"
137+ if (random () %100 < cfg.updatePercent ) {
138+ int rc = cfg.prepared
139+ ? txn.prepared (" transfer" 1 )(srcAcc).exec ().affected_rows ()
140+ :exec (txn," update t set v = v - 1 where u=%d"
141+ if (rc !=1 ) {
142+ printf (" Failed to withdraw from account %d\n "
143+ }
144+ rc = cfg.prepared
145+ ? txn.prepared (" transfer" 1 )(dstAcc).exec ().affected_rows ()
146+ :exec (txn," update t set v = v + 1 where u=%d"
147+ if (rc !=1 ) {
148+ printf (" Failed to deposit to account %d\n "
149+ }
135150 t.updates +=2 ;
136151 }else {
137152int64_t sum = execQuery<int64_t >(txn," select v from t where u=%d"
@@ -158,7 +173,7 @@ void initializeDatabase()
158173 connectionconn (cfg.connection );
159174if (cfg.nShards ==0 ) {
160175worktxn (conn);
161- exec (txn," insert into t (select generate_series(1 ,%d), 0)" nAccounts );
176+ exec (txn," insert into t (select generate_series(0 ,%d), 0)" nAccounts - 1 );
162177txn.commit ();
163178}else {
164179int accountsPerShard = (cfg.nAccounts + cfg.nShards -1 )/cfg.nShards ;
@@ -206,6 +221,9 @@ int main (int argc, char* argv[])
206221 initialize =true ;
207222cfg.nShards =atoi (argv[++i]);
208223continue ;
224+ case ' P'
225+ cfg.prepared =true ;
226+ continue ;
209227 }
210228 }
211229printf (" Options:\n "
@@ -215,7 +233,8 @@ int main (int argc, char* argv[])
215233" \t -n N\t number of iterations (1000)\n "
216234" \t -p N\t update percent (100)\n "
217235" \t -c STR\t database connection string\n "
218- " \t -i N\t initialize N shards\n "
236+ " \t -i N\t initialize N shards\n "
237+ " \t -P\t use prepared statements\n "
219238return 1 ;
220239 }
221240
@@ -263,7 +282,7 @@ int main (int argc, char* argv[])
263282printf (
264283" {\" tps\" :%f,\" transactions\" :%ld,"
265284" \" selects\" :%ld,\" updates\" :%ld,\" aborts\" :%ld,\" abort_percent\" : %d,"
266- " \" readers\" :%d,\" writers\" :%d,\" update_percent\" :%d,\" accounts\" :%d,\" iterations\" :%d ,\" shards\" :%d}\n "
285+ " \" readers\" :%d,\" writers\" :%d,\" update_percent\" :%d,\" accounts\" :%d,\" iterations\" :%d ,\" shards\" :%d, \" prepared \" :%d }\n "
267286 (double )(nTransactions*USEC)/elapsed,
268287 nTransactions,
269288 nSelects,
@@ -275,7 +294,8 @@ int main (int argc, char* argv[])
275294 cfg.updatePercent ,
276295 cfg.nAccounts ,
277296 cfg.nIterations ,
278- cfg.nShards );
297+ cfg.nShards ,
298+ cfg.prepared );
279299
280300return 0 ;
281301}