| 1 | /* |
| 2 | * rcuja/testpop.c |
| 3 | * |
| 4 | * Userspace RCU library - RCU Judy Array population size test |
| 5 | * |
| 6 | * Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 7 | * |
| 8 | * This library is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; either |
| 11 | * version 2.1 of the License, or (at your option) any later version. |
| 12 | * |
| 13 | * This library is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with this library; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | /* |
| 24 | * This program generates random populations, and shows the worse-case |
| 25 | * unbalance, as well as the distribution of unbalance encountered. |
| 26 | * Remember that the unbalance is the delta between the lowest and |
| 27 | * largest population. Therefore, to get the delta between the subclass |
| 28 | * size and the actual number of items, we need to divide the unbalance |
| 29 | * by the number of subclasses (by hand). |
| 30 | */ |
| 31 | |
| 32 | #include <stdio.h> |
| 33 | #include <stdlib.h> |
| 34 | #include <stdint.h> |
| 35 | #include <time.h> |
| 36 | #include <string.h> |
| 37 | #include <limits.h> |
| 38 | |
| 39 | static int sel_pool_len = 50; /* default */ |
| 40 | static int nr_distrib = 2; /* default */ |
| 41 | //#define SEL_POOL_LEN 100 |
| 42 | //#define NR_POOLS 10000000ULL |
| 43 | |
| 44 | static uint8_t pool[256]; |
| 45 | static uint8_t nr_one[8]; |
| 46 | static uint8_t nr_2d_11[8][8]; |
| 47 | static uint8_t nr_2d_10[8][8]; |
| 48 | static int global_max_minunbalance = 0; |
| 49 | |
| 50 | static unsigned int unbalance_distrib[256]; |
| 51 | |
| 52 | static |
| 53 | uint8_t random_char(void) |
| 54 | { |
| 55 | return (uint8_t) random(); |
| 56 | } |
| 57 | |
| 58 | static |
| 59 | void print_pool(void) |
| 60 | { |
| 61 | int i; |
| 62 | |
| 63 | printf("pool: "); |
| 64 | for (i = 0; i < sel_pool_len; i++) { |
| 65 | printf("%d ", (int) pool[i]); |
| 66 | } |
| 67 | printf("\n"); |
| 68 | } |
| 69 | |
| 70 | static |
| 71 | void gen_pool(void) |
| 72 | { |
| 73 | uint8_t src_pool[256]; |
| 74 | int i; |
| 75 | int nr_left = 256; |
| 76 | |
| 77 | memset(pool, 0, sizeof(pool)); |
| 78 | for (i = 0; i < 256; i++) |
| 79 | src_pool[i] = (uint8_t) i; |
| 80 | for (i = 0; i < sel_pool_len; i++) { |
| 81 | int sel; |
| 82 | |
| 83 | sel = random_char() % nr_left; |
| 84 | pool[i] = src_pool[sel]; |
| 85 | src_pool[sel] = src_pool[nr_left - 1]; |
| 86 | nr_left--; |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | static |
| 91 | void count_pool(void) |
| 92 | { |
| 93 | int i; |
| 94 | |
| 95 | memset(nr_one, 0, sizeof(nr_one)); |
| 96 | memset(nr_2d_11, 0, sizeof(nr_2d_11)); |
| 97 | memset(nr_2d_10, 0, sizeof(nr_2d_10)); |
| 98 | for (i = 0; i < sel_pool_len; i++) { |
| 99 | if (nr_distrib == 2) { |
| 100 | int j; |
| 101 | |
| 102 | for (j = 0; j < 8; j++) { |
| 103 | if (pool[i] & (1U << j)) |
| 104 | nr_one[j]++; |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | if (nr_distrib == 4) { |
| 109 | int j, k; |
| 110 | |
| 111 | for (j = 0; j < 8; j++) { |
| 112 | for (k = 0; k < j; k++) { |
| 113 | if ((pool[i] & (1U << j)) && (pool[i] & (1U << k))) { |
| 114 | nr_2d_11[j][k]++; |
| 115 | } |
| 116 | if ((pool[i] & (1U << j)) && !(pool[i] & (1U << k))) { |
| 117 | nr_2d_10[j][k]++; |
| 118 | } |
| 119 | } |
| 120 | } |
| 121 | } |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | static |
| 126 | void print_count(void) |
| 127 | { |
| 128 | int i; |
| 129 | |
| 130 | printf("pool distribution:\n"); |
| 131 | |
| 132 | if (nr_distrib == 2) { |
| 133 | printf(" 0 1\n"); |
| 134 | printf("----------\n"); |
| 135 | for (i = 0; i < 8; i++) { |
| 136 | printf("%3d %3d\n", |
| 137 | sel_pool_len - nr_one[i], nr_one[i]); |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | if (nr_distrib == 4) { |
| 142 | /* TODO */ |
| 143 | } |
| 144 | printf("\n"); |
| 145 | } |
| 146 | |
| 147 | static |
| 148 | void stat_count(void) |
| 149 | { |
| 150 | int minunbalance = INT_MAX; |
| 151 | |
| 152 | if (nr_distrib == 2) { |
| 153 | int i; |
| 154 | |
| 155 | for (i = 0; i < 8; i++) { |
| 156 | int diff; |
| 157 | |
| 158 | diff = (int) nr_one[i] * 2 - sel_pool_len; |
| 159 | if (diff < 0) |
| 160 | diff = -diff; |
| 161 | if (diff < minunbalance) { |
| 162 | minunbalance = diff; |
| 163 | } |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | if (nr_distrib == 4) { |
| 168 | int j, k; |
| 169 | |
| 170 | for (j = 0; j < 8; j++) { |
| 171 | for (k = 0; k < j; k++) { |
| 172 | int diff[2]; |
| 173 | |
| 174 | diff[0] = (int) nr_2d_11[j][k] * 4 - sel_pool_len; |
| 175 | if (diff[0] < 0) |
| 176 | diff[0] = -diff[0]; |
| 177 | |
| 178 | diff[1] = (int) nr_2d_10[j][k] * 4 - sel_pool_len; |
| 179 | if (diff[1] < 0) |
| 180 | diff[1] = -diff[1]; |
| 181 | /* Get max linear array size */ |
| 182 | if (diff[1] > diff[0]) |
| 183 | diff[0] = diff[1]; |
| 184 | if (diff[0] < minunbalance) { |
| 185 | minunbalance = diff[0]; |
| 186 | } |
| 187 | } |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | if (minunbalance > global_max_minunbalance) { |
| 192 | global_max_minunbalance = minunbalance; |
| 193 | } |
| 194 | unbalance_distrib[minunbalance]++; |
| 195 | } |
| 196 | |
| 197 | static |
| 198 | void print_distrib(void) |
| 199 | { |
| 200 | int i; |
| 201 | unsigned long long tot = 0; |
| 202 | |
| 203 | for (i = 0; i < 256; i++) { |
| 204 | tot += unbalance_distrib[i]; |
| 205 | } |
| 206 | if (tot == 0) |
| 207 | return; |
| 208 | printf("Distribution:\n"); |
| 209 | for (i = 0; i < 256; i++) { |
| 210 | printf("(%u, %u, %llu%%) ", |
| 211 | i, unbalance_distrib[i], |
| 212 | 100 * (unsigned long long) unbalance_distrib[i] / tot); |
| 213 | } |
| 214 | printf("\n"); |
| 215 | } |
| 216 | |
| 217 | static |
| 218 | void print_stat(uint64_t i) |
| 219 | { |
| 220 | printf("after %llu pools, global_max_minunbalance: %d\n", |
| 221 | (unsigned long long) i, global_max_minunbalance); |
| 222 | print_distrib(); |
| 223 | } |
| 224 | |
| 225 | int main(int argc, char **argv) |
| 226 | { |
| 227 | uint64_t i = 0; |
| 228 | |
| 229 | srandom(time(NULL)); |
| 230 | |
| 231 | if (argc > 1) { |
| 232 | sel_pool_len = atoi(argv[1]); |
| 233 | if (sel_pool_len > 256 || sel_pool_len < 1) { |
| 234 | printf("Wrong pool len\n"); |
| 235 | return -1; |
| 236 | } |
| 237 | } |
| 238 | printf("pool len: %d\n", sel_pool_len); |
| 239 | |
| 240 | if (argc > 2) { |
| 241 | nr_distrib = atoi(argv[2]); |
| 242 | if (nr_distrib > 256 || nr_distrib < 1) { |
| 243 | printf("Wrong number of distributions\n"); |
| 244 | return -1; |
| 245 | } |
| 246 | } |
| 247 | printf("pool distributions: %d\n", nr_distrib); |
| 248 | |
| 249 | if (nr_distrib != 2 && nr_distrib != 4) { |
| 250 | printf("Wrong number of distributions. Only 2 and 4 supported.\n"); |
| 251 | return -1; |
| 252 | } |
| 253 | |
| 254 | //for (i = 0; i < NR_POOLS; i++) { |
| 255 | while (1) { |
| 256 | gen_pool(); |
| 257 | count_pool(); |
| 258 | //print_pool(); |
| 259 | //print_count(); |
| 260 | stat_count(); |
| 261 | if (!(i % 100000ULL)) |
| 262 | print_stat(i); |
| 263 | i++; |
| 264 | } |
| 265 | print_stat(i); |
| 266 | print_distrib(); |
| 267 | |
| 268 | return 0; |
| 269 | } |