*** a/contrib/pgbench/pgbench.c --- b/contrib/pgbench/pgbench.c *************** *** 41,46 **** --- 41,47 ---- #include #include #include + #include #ifdef HAVE_SYS_SELECT_H #include #endif *************** *** 157,162 **** char *index_tablespace = NULL; --- 158,164 ---- * document and remember, and isn't that far away from the real threshold. */ #define SCALE_32BIT_THRESHOLD 20000 + #define MIN_GAUSSIAN_THRESHOLD 2.0 bool use_log; /* log transaction latencies to a file */ bool use_quiet; /* quiet logging onto stderr */ *************** *** 171,176 **** bool is_connect; /* establish connection for each transaction */ --- 173,183 ---- bool is_latencies; /* report per-command latencies */ int main_pid; /* main process id used in log filename */ + /* gaussian/exponential distribution tests */ + double threshold; /* threshold for gaussian or exponential */ + bool use_gaussian = false; + bool use_exponential = false; + char *pghost = ""; char *pgport = ""; char *login = NULL; *************** *** 292,302 **** static int num_commands = 0; /* total number of Command structs */ static int debug = 0; /* debug flag */ /* default scenario */ ! static char *tpc_b = { "\\set nbranches " CppAsString2(nbranches) " * :scale\n" "\\set ntellers " CppAsString2(ntellers) " * :scale\n" "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts\n" "\\setrandom bid 1 :nbranches\n" "\\setrandom tid 1 :ntellers\n" "\\setrandom delta -5000 5000\n" --- 299,309 ---- static int debug = 0; /* debug flag */ /* default scenario */ ! static char *tpc_b_fmt = { "\\set nbranches " CppAsString2(nbranches) " * :scale\n" "\\set ntellers " CppAsString2(ntellers) " * :scale\n" "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts%s\n" "\\setrandom bid 1 :nbranches\n" "\\setrandom tid 1 :ntellers\n" "\\setrandom delta -5000 5000\n" *************** *** 310,320 **** static char *tpc_b = { }; /* -N case */ ! static char *simple_update = { "\\set nbranches " CppAsString2(nbranches) " * :scale\n" "\\set ntellers " CppAsString2(ntellers) " * :scale\n" "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts\n" "\\setrandom bid 1 :nbranches\n" "\\setrandom tid 1 :ntellers\n" "\\setrandom delta -5000 5000\n" --- 317,327 ---- }; /* -N case */ ! static char *simple_update_fmt = { "\\set nbranches " CppAsString2(nbranches) " * :scale\n" "\\set ntellers " CppAsString2(ntellers) " * :scale\n" "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts%s\n" "\\setrandom bid 1 :nbranches\n" "\\setrandom tid 1 :ntellers\n" "\\setrandom delta -5000 5000\n" *************** *** 326,334 **** static char *simple_update = { }; /* -S case */ ! static char *select_only = { "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts\n" "SELECT abalance FROM pgbench_accounts WHERE aid = :aid;\n" }; --- 333,341 ---- }; /* -S case */ ! static char *select_only_fmt = { "\\set naccounts " CppAsString2(naccounts) " * :scale\n" ! "\\setrandom aid 1 :naccounts%s\n" "SELECT abalance FROM pgbench_accounts WHERE aid = :aid;\n" }; *************** *** 375,380 **** usage(void) --- 382,389 ---- " -v, --vacuum-all vacuum all four standard tables before tests\n" " --aggregate-interval=NUM aggregate data over NUM seconds\n" " --sampling-rate=NUM fraction of transactions to log (e.g. 0.01 for 1%%)\n" + " --exponential=NUM exponential distribution with NUM threshold parameter\n" + " --gaussian=NUM gaussian distribution with NUM threshold parameter\n" "\nCommon options:\n" " -d, --debug print debugging output\n" " -h, --host=HOSTNAME database server host or socket directory\n" *************** *** 2178,2183 **** process_builtin(char *tb) --- 2187,2216 ---- return my_commands; } + /* + * compute the probability of the truncated gaussian random generation + * to draw values in the i-th slot of the range. + */ + static double gaussianProbability(int i, int slots, double threshold) + { + assert(1 <= i && i <= slots); + return (0.50 * (erf (threshold * (1.0 - 1.0 / slots * (2.0 * i - 2.0)) / sqrt(2.0)) - + erf (threshold * (1.0 - 1.0 / slots * 2.0 * i) / sqrt(2.0))) / + erf (threshold / sqrt(2.0))); + } + + /* + * compute the probability of the truncated exponential random generation + * to draw values in the i-th slot of the range. + */ + static double exponentialProbability(int i, int slots, double threshold) + { + assert(1 <= i && i <= slots); + return (exp(- threshold * (i - 1) / slots) - exp(- threshold * i / slots)) / + (1.0 - exp(- threshold)); + } + + /* print out results */ static void printResults(int ttype, int64 normal_xacts, int nclients, *************** *** 2189,2195 **** printResults(int ttype, int64 normal_xacts, int nclients, double time_include, tps_include, tps_exclude; ! char *s; time_include = INSTR_TIME_GET_DOUBLE(total_time); tps_include = normal_xacts / time_include; --- 2222,2228 ---- double time_include, tps_include, tps_exclude; ! char *s, *d; time_include = INSTR_TIME_GET_DOUBLE(total_time); tps_include = normal_xacts / time_include; *************** *** 2205,2212 **** printResults(int ttype, int64 normal_xacts, int nclients, else s = "Custom query"; ! printf("transaction type: %s\n", s); printf("scaling factor: %d\n", scale); printf("query mode: %s\n", QUERYMODE[querymode]); printf("number of clients: %d\n", nclients); printf("number of threads: %d\n", nthreads); --- 2238,2283 ---- else s = "Custom query"; ! if (use_gaussian) ! d = "Gaussian distribution "; ! else if (use_exponential) ! d = "Exponential distribution "; ! else ! d = ""; /* default uniform case */ ! ! printf("transaction type: %s%s\n", d, s); printf("scaling factor: %d\n", scale); + + /* output in gaussian distribution benchmark */ + if (use_gaussian) + { + int i; + printf("pgbench_account's aid selected with a truncated gaussian distribution\n"); + printf("standard deviation threshold: %.5f\n", threshold); + printf("decile percents:"); + for (i = 1; i <= 10; i++) + printf(" %.1f%%", 100.0 * gaussianProbability(i, 10.0, threshold)); + printf("\n"); + printf("probability of max/min percent of the range: %.1f%% %.1f%%\n", + 100.0 * gaussianProbability(50, 100, threshold), + 100.0 * gaussianProbability(100, 100, threshold)); + } + /* output in exponential distribution benchmark */ + else if (use_exponential) + { + int i; + printf("pgbench_account's aid selected with a truncated exponential distribution\n"); + printf("exponential threshold: %.5f\n", threshold); + printf("decile percents:"); + for (i = 1; i <= 10; i++) + printf(" %.1f%%", + 100.0 * exponentialProbability(i, 10, threshold)); + printf("\n"); + printf("probability of fist/last percent of the range: %.1f%% %.1f%%\n", + 100.0 * exponentialProbability(1, 100, threshold), + 100.0 * exponentialProbability(100, 100, threshold)); + } + printf("query mode: %s\n", QUERYMODE[querymode]); printf("number of clients: %d\n", nclients); printf("number of threads: %d\n", nthreads); *************** *** 2337,2342 **** main(int argc, char **argv) --- 2408,2415 ---- {"unlogged-tables", no_argument, &unlogged_tables, 1}, {"sampling-rate", required_argument, NULL, 4}, {"aggregate-interval", required_argument, NULL, 5}, + {"gaussian", required_argument, NULL, 6}, + {"exponential", required_argument, NULL, 7}, {"rate", required_argument, NULL, 'R'}, {NULL, 0, NULL, 0} }; *************** *** 2617,2622 **** main(int argc, char **argv) --- 2690,2714 ---- } #endif break; + case 6: + use_gaussian = true; + threshold = atof(optarg); + if(threshold < MIN_GAUSSIAN_THRESHOLD) + { + fprintf(stderr, "--gaussian=NUM must be more than %f: %f\n", + MIN_GAUSSIAN_THRESHOLD, threshold); + exit(1); + } + break; + case 7: + use_exponential = true; + threshold = atof(optarg); + if(threshold <= 0.0) + { + fprintf(stderr, "--exponential=NUM must be more than 0.0\n"); + exit(1); + } + break; default: fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); exit(1); *************** *** 2814,2819 **** main(int argc, char **argv) --- 2906,2922 ---- } } + /* set :threshold variable */ + if(getVariable(&state[0], "threshold") == NULL) + { + snprintf(val, sizeof(val), "%lf", threshold); + for (i = 0; i < nclients; i++) + { + if (!putVariable(&state[i], "startup", "threshold", val)) + exit(1); + } + } + if (!is_no_vacuum) { fprintf(stderr, "starting vacuum..."); *************** *** 2836,2860 **** main(int argc, char **argv) srandom((unsigned int) INSTR_TIME_GET_MICROSEC(start_time)); /* process builtin SQL scripts */ ! switch (ttype) { ! case 0: ! sql_files[0] = process_builtin(tpc_b); ! num_files = 1; ! break; ! ! case 1: ! sql_files[0] = process_builtin(select_only); ! num_files = 1; ! break; ! ! case 2: ! sql_files[0] = process_builtin(simple_update); ! num_files = 1; ! break; ! ! default: ! break; } /* set up thread data structures */ --- 2939,2962 ---- srandom((unsigned int) INSTR_TIME_GET_MICROSEC(start_time)); /* process builtin SQL scripts */ ! if (ttype < 3) { ! char *fmt, *distribution, *queries; ! int ret; ! fmt = (ttype == 0)? tpc_b_fmt: ! (ttype == 1)? select_only_fmt: ! (ttype == 2)? simple_update_fmt: NULL; ! assert(fmt != NULL); ! distribution = ! use_gaussian? " gaussian :threshold": ! use_exponential? " exponential :threshold": ! "" /* default uniform case */ ; ! queries = pg_malloc(strlen(fmt) + strlen(distribution) + 1); ! ret = sprintf(queries, fmt, distribution); ! assert(ret >= 0); ! sql_files[0] = process_builtin(queries); ! num_files = 1; ! pg_free(queries); } /* set up thread data structures */ *** a/doc/src/sgml/pgbench.sgml --- b/doc/src/sgml/pgbench.sgml *************** *** 307,312 **** pgbench options dbname --- 307,355 ---- + threshold + + + Run exponential distribution pgbench test using this threshold parameter. + The threshold controls the distribution of access frequency on the + pgbench_accounts table. + See the \setrandom documentation below for details about + the impact of the threshold value. + When set, this option applies to all test variants ( + + + When run, the output is expanded to show the distribution + depending on the threshold value: + + + ... + pgbench_account's aid selected with a truncated exponential distribution + exponential threshold: 5.00000 + decile percents: 39.6% 24.0% 14.6% 8.8% 5.4% 3.3% 2.0% 1.2% 0.7% 0.4% + probability of fist/last percent of the range: 4.9% 0.0% + ... + + + The figures are to be interpreted as follows. + If the scaling factor is 10, there are 1,000,000 accounts in + pgbench_accounts. + The first decile, with aid from 1 to 100,000, is + drawn 39.6% of the time, that is about 4 times more than average. + The second decile, from 100,001 to 200,000 is drawn 24.0% of the time, + that is 2.4 times more than average. + Up to the last decile, from 900,001 to 1,000,000, which is drawn + 0.4% of the time, well below average. + Moreover, the first percent of the range, that is aid + from 1 to 10,000, is drawn 4.9% of the time, this 4.9 times more + than average, and the last percent, with aid + from 990,001 to 1,000,000, is drawn less than 0.1% of the time. + + + + + filename filename *************** *** 320,325 **** pgbench options dbname --- 363,411 ---- + threshold + + + Run gaussian distribution pgbench test using this threshold parameter. + The threshold controls the distribution of access frequency on the + pgbench_accounts table. + See the \setrandom documentation below for details about + the impact of the threshold value. + When set, this option applies to all test variants ( + + + When run, the output is expanded to show the distribution + depending on the threshold value: + + + ... + pgbench_account's aid selected with a truncated gaussian distribution + standard deviation threshold: 5.00000 + decile percents: 0.0% 0.1% 2.1% 13.6% 34.1% 34.1% 13.6% 2.1% 0.1% 0.0% + probability of max/min percent of the range: 4.0% 0.0% + ... + + + The figures are to be interpreted as follows. + If the scaling factor is 10, there are 1,000,000 accounts in + pgbench_accounts. + The first decile, with aid from 1 to 100,000, is + drawn less than 0.1% of the time. + The second, from 100,001 to 200,000 is drawn about 0.1% of the time... + up to the fifth decile, from 400,001 to 500,000, which + is drawn 34.1% of the time, about 3.4 times more thn average, + and then the gaussian curve is symmetric for the last five deciles. + Moreover, the first percent of the range, that is aid + from 50,001 to 60,000, is drawn 4.0% of the time, this 4.0 times more + than average, and the last percent, with aid + from 990,001 to 1,000,000, is drawn less than 0.1% of the time. + + + + + threads threads