memory_pressure.tproj/memory_pressure.c

   1 /*
   2  * Copyright (c) 2013-2016 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <errno.h>
  27 #include <getopt.h>
  28 #include <string.h>
  29 #include <mach/i386/vm_param.h>
  30 #include <sys/kern_memorystatus.h>
  31 #include <sys/sysctl.h>
  32 #include <mach/mach.h>
  33 #include <mach/task.h>
  34 #include <mach/thread_act.h>
  35 #include <mach/thread_policy.h>
  36 #include <sys/mman.h>
  37 #include <pthread.h>
  38 #include <assert.h>
  39 #include <dispatch/private.h>
  40
  41 unsigned long   phys_mem = 0;            /* amount of physical memory in bytes */
  42 unsigned int    phys_pages = 0;          /* number of physical memory pages */
  43 int             sleep_seconds = 1;
  44 boolean_t       quiet_mode_on = FALSE;
  45 boolean_t       simulate_mode_on = FALSE;
  46
  47 void            *range_start_addr = NULL;
  48 void            *range_end_addr = NULL;
  49 void            *range_current_addr = NULL;
  50
  51 int                     start_referencing_pages = 0;
  52 int                     start_allocing_pages = 0;
  53 pthread_cond_t          reference_pages_condvar = PTHREAD_COND_INITIALIZER;
  54 pthread_mutex_t         reference_pages_mutex = PTHREAD_MUTEX_INITIALIZER;
  55 unsigned int            desired_level = 0, desired_percent = 0;
  56 unsigned int            percent_for_level = 0;
  57 int                     tool_mode = 0;
  58
  59 #define TOOL_MODE_FOR_PERCENT   1
  60 #define TOOL_MODE_FOR_LEVEL     2
  61
  62
  63 char            random_data[] = "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";
  64
  65 #define PAGE_OP_ALLOC   0x1
  66 #define PAGE_OP_FREE    0x2
  67
  68 #define USE_WIRED_PAGES_FOR_PERCENT_MODE        FALSE
  69
  70 #define MAX_RANGE_SIZE  64 * 1024 * 1024 * 1024ULL
  71
  72 void print_vm_statistics(void);
  73 void munch_for_level(unsigned int, unsigned int);
  74 void munch_for_percentage(unsigned int, unsigned int, unsigned int);
  75
  76 static void
  77 usage(void)
  78 {
  79         fprintf(stderr, "Usage: memory_pressure [options] [<pages>]\n"
  80                         "  Allocate memory and wait forever.\n"
  81                         "  Options include:\n"
  82                         "  -l <level>            - allocate memory until a low memory notification is received (warn OR critical)\n"
  83                         "  -p <percent-free>     - allocate memory until percent free is this (or less)\n"
  84                         "  -s <seconds>          - how long to sleep between checking for a set percent level\n"
  85                         "  -w <percent-free>     - don't allocate, just wait until percent free is this then exit\n"
  86                         "  -v <print VM stats>   - print VM statistics every sampling interval\n"
  87                         "  -Q <quiet mode>       - reduces the tool's output\n"
  88                         "  -S                    - simulate the system's memory pressure level without applying any real pressure\n"
  89                         "  \n"
  90                );
  91         exit(0);
  92 }
  93
  94 static unsigned int
  95 read_sysctl_int(const char* name)
  96 {
  97         unsigned int var;
  98         size_t var_size;
  99         int error;
 100
 101         var_size = sizeof(var);
 102         error = sysctlbyname(name, &var, &var_size, NULL, 0);
 103         if( error ) {
 104                 perror(name);
 105                 exit(-1);
 106         }
 107         return var;
 108 }
 109
 110 static int
 111 get_percent_free(unsigned int* level)
 112 {
 113         int error;
 114
 115         error = memorystatus_get_level((user_addr_t) level);
 116
 117         if( error ) {
 118                 perror("memorystatus_get_level failed:");
 119                 exit(-1);
 120         }
 121         return error;
 122 }
 123
 124 void
 125 print_vm_statistics(void)
 126 {
 127         unsigned int count = HOST_VM_INFO64_COUNT;
 128         kern_return_t ret = 0;
 129         vm_statistics64_data_t vm_stat;;
 130
 131         if (quiet_mode_on == TRUE) {
 132                 return;
 133         }
 134
 135         if ((ret = host_statistics64(mach_host_self(), HOST_VM_INFO64, (host_info64_t)&vm_stat, &count) != KERN_SUCCESS)) {
 136                 fprintf(stderr, "Failed to get statistics. Error %d\n", ret);
 137         } else {
 138                 printf("\nStats: \n");
 139                 printf("Pages free: %llu \n", (uint64_t) (vm_stat.free_count - vm_stat.speculative_count));
 140                 printf("Pages purgeable: %llu \n",  (uint64_t) (vm_stat.purgeable_count));
 141                 printf("Pages purged: %llu \n",(uint64_t) (vm_stat.purges));
 142
 143                 printf("\nSwap I/O:\n");
 144                 printf("Swapins: %llu \n", (uint64_t) (vm_stat.swapins));
 145                 printf("Swapouts: %llu \n", (uint64_t) (vm_stat.swapouts));
 146
 147                 printf("\nPage Q counts:\n");
 148                 printf("Pages active: %llu \n", (uint64_t) (vm_stat.active_count));
 149                 printf("Pages inactive: %llu \n", (uint64_t) (vm_stat.inactive_count));
 150                 printf("Pages speculative: %llu \n", (uint64_t) (vm_stat.speculative_count));
 151                 printf("Pages throttled: %llu \n", (uint64_t) (vm_stat.throttled_count));
 152                 printf("Pages wired down: %llu \n", (uint64_t) (vm_stat.wire_count));
 153
 154                 printf("\nCompressor Stats:\n");
 155                 printf("Pages used by compressor: %llu \n", (uint64_t) (vm_stat.compressor_page_count));
 156                 printf("Pages decompressed: %llu \n", (uint64_t) (vm_stat.decompressions));
 157                 printf("Pages compressed: %llu \n", (uint64_t) (vm_stat.compressions));
 158
 159                 printf("\nFile I/O:\n");
 160                 printf("Pageins: %llu \n", (uint64_t) (vm_stat.pageins));
 161                 printf("Pageouts: %llu \n", (uint64_t) (vm_stat.pageouts));
 162
 163 #if 0
 164                 printf("\"Translation faults\": %llu \n", (uint64_t) (vm_stat.faults));
 165                 printf("Pages copy-on-write: %llu \n", (uint64_t) (vm_stat.cow_faults));
 166                 printf("Pages zero filled: %llu \n", (uint64_t) (vm_stat.zero_fill_count));
 167                 printf("Pages reactivated: %llu \n", (uint64_t) (vm_stat.reactivations));
 168 #endif
 169                 printf("\n");
 170         }
 171 }
 172
 173 static int
 174 reached_or_bypassed_desired_result(void)
 175 {
 176         if (tool_mode == TOOL_MODE_FOR_LEVEL) {
 177
 178                 unsigned int    current_level = 0;
 179
 180                 current_level = read_sysctl_int("kern.memorystatus_vm_pressure_level");
 181
 182                 if (desired_level > 0 && current_level >= desired_level) {
 183                        return 1;
 184                 }
 185
 186                 return 0;
 187         }
 188
 189         if (tool_mode == TOOL_MODE_FOR_PERCENT) {
 190
 191                 unsigned int current_percent = 0;
 192
 193                 get_percent_free(&current_percent);
 194
 195                 if (desired_percent > 0 && current_percent <= desired_percent) {
 196                         return 1;
 197                 }
 198
 199                 return 0;
 200         }
 201
 202         return 0;
 203 }
 204
 205 static void
 206 reference_pages(int level)
 207 {
 208         int     error;
 209         void    *addr = NULL;
 210         int     num_pages = 0;
 211
 212         error = pthread_mutex_lock(&reference_pages_mutex);
 213         addr = range_start_addr;
 214 again:
 215         while(start_referencing_pages == 0) {
 216                 error = pthread_cond_wait(&reference_pages_condvar, &reference_pages_mutex);
 217         }
 218
 219         start_allocing_pages = 0;
 220         pthread_mutex_unlock(&reference_pages_mutex);
 221
 222         num_pages = 0;
 223         for(; addr < range_current_addr;) {
 224
 225                 char p;
 226
 227                 if (reached_or_bypassed_desired_result()) {
 228                         //printf("stopped referencing after %d pages\n", num_pages);
 229                         break;
 230                 }
 231
 232                 p = *(char*) addr;
 233                 addr += PAGE_SIZE;
 234                 num_pages++;
 235
 236         }
 237
 238         //if (num_pages) {
 239         //      printf("Referenced %d\n", num_pages);
 240         //}
 241         error = pthread_mutex_lock(&reference_pages_mutex);
 242         start_referencing_pages = 0;
 243         start_allocing_pages = 1;
 244
 245         goto again;
 246 }
 247
 248 static void
 249 process_pages(int num_pages, int page_op)
 250 {
 251         if (num_pages > 0) {
 252
 253                 int     error = 0, i = 0;
 254                 size_t  size = num_pages * PAGE_SIZE;
 255
 256                 if (page_op == PAGE_OP_ALLOC) {
 257
 258                         if (tool_mode == TOOL_MODE_FOR_PERCENT && USE_WIRED_PAGES_FOR_PERCENT_MODE) {
 259                                 error = mlock(range_current_addr, size);
 260                                 if (error == -1) {
 261                                         perror("Failed to lock memory!");
 262                                         exit(-1);
 263                                 }
 264
 265                                 memset(range_current_addr, 0xFF, size);
 266                                 range_current_addr += size;
 267
 268                         } else {
 269
 270                                 pthread_mutex_lock(&reference_pages_mutex);
 271                                 while (start_allocing_pages == 0) {
 272                                         pthread_mutex_unlock(&reference_pages_mutex);
 273                                         sleep(1);
 274                                         pthread_mutex_lock(&reference_pages_mutex);
 275                                 }
 276                                 pthread_mutex_unlock(&reference_pages_mutex);
 277
 278                                 for (i=0; i < num_pages; i++) {
 279
 280                                         if (reached_or_bypassed_desired_result()) {
 281                                                 //printf("stopped faulting after %d pages\n", i);
 282                                                 break;
 283                                         }
 284
 285                                         memcpy(range_current_addr, random_data, PAGE_SIZE);
 286                                         range_current_addr += PAGE_SIZE;
 287                                 }
 288
 289                                 pthread_mutex_lock(&reference_pages_mutex);
 290                                 start_referencing_pages = 1;
 291                                 pthread_cond_signal(&reference_pages_condvar);
 292                                 pthread_mutex_unlock(&reference_pages_mutex);
 293                         }
 294                 } else {
 295                         if (tool_mode == TOOL_MODE_FOR_PERCENT && USE_WIRED_PAGES_FOR_PERCENT_MODE) {
 296                                 error = munlock(range_current_addr, size);
 297                                 if (error == -1) {
 298                                         perror("Failed to unlock memory!");
 299                                         exit(-1);
 300                                 }
 301
 302                                 error = madvise(range_current_addr, size, MADV_FREE);
 303                                 if (error == -1) {
 304                                         perror("Failed to madv_free memory!");
 305                                         exit(-1);
 306                                 }
 307
 308                                 range_current_addr -= size;
 309
 310                         } else {
 311                                 pthread_mutex_lock(&reference_pages_mutex);
 312                                 while (start_referencing_pages == 1) {
 313                                         pthread_mutex_unlock(&reference_pages_mutex);
 314                                         sleep(1);
 315                                         pthread_mutex_lock(&reference_pages_mutex);
 316                                 }
 317
 318                                 error = madvise(range_current_addr, size, MADV_FREE);
 319                                 if (error == -1) {
 320                                         perror("Failed to madv_free memory!");
 321                                         exit(-1);
 322                                 }
 323                                 range_current_addr -= size;
 324                                 start_referencing_pages = 1;
 325                                 pthread_cond_signal(&reference_pages_condvar);
 326                                 pthread_mutex_unlock(&reference_pages_mutex);
 327                         }
 328                 }
 329         }
 330 }
 331
 332 void
 333 munch_for_level(unsigned int sleep_seconds, unsigned int print_vm_stats)
 334 {
 335
 336         unsigned int    current_level = 0;
 337         unsigned int    desired_percent = 0;
 338         unsigned int    current_percent = 0;
 339         unsigned int    page_op = PAGE_OP_ALLOC;
 340         unsigned int    previous_page_op = PAGE_OP_ALLOC;
 341         unsigned int    pages_to_process = 0;
 342         unsigned int    stabilized_percentage = 0;
 343         boolean_t       print_vm_stats_on_page_processing = FALSE;
 344         boolean_t       ok_to_print_stablity_message = TRUE;
 345
 346         current_level =  read_sysctl_int("kern.memorystatus_vm_pressure_level");
 347
 348         if (current_level >= desired_level) {
 349                 return;
 350         }
 351
 352         get_percent_free(&current_percent);
 353
 354         if (print_vm_stats) {
 355                 print_vm_stats_on_page_processing = TRUE;
 356         }
 357
 358         page_op = PAGE_OP_ALLOC;
 359         previous_page_op = 0;
 360
 361         while (1) {
 362
 363                         if (current_percent > percent_for_level) {
 364                                 desired_percent = current_percent - percent_for_level;
 365                         } else {
 366                                 desired_percent = 1;
 367                         }
 368
 369                         pages_to_process = (desired_percent * phys_pages) / 100;
 370
 371                         page_op = PAGE_OP_ALLOC;
 372
 373                         if (previous_page_op != page_op) {
 374                                 //printf("%s %d pages.\n", (page_op == PAGE_OP_ALLOC) ? "Allocating" : "Freeing", pages_to_process);
 375                                 printf("\nCMD: %s pages to go from level: %d to level: %d", (page_op == PAGE_OP_ALLOC) ? "Allocating" : "Freeing", current_level, desired_level);
 376                                 previous_page_op = page_op;
 377                                 fflush(stdout);
 378                         } else {
 379                                 printf(".");
 380                                 fflush(stdout);
 381                         }
 382
 383                         if (print_vm_stats_on_page_processing == TRUE) {
 384                                 print_vm_statistics();
 385                         }
 386                         process_pages(pages_to_process, page_op);
 387                         ok_to_print_stablity_message = TRUE;
 388
 389                         current_level =  read_sysctl_int("kern.memorystatus_vm_pressure_level");
 390
 391                         if (current_level >= desired_level) {
 392
 393                                 while(1) {
 394                                         current_level =  read_sysctl_int("kern.memorystatus_vm_pressure_level");
 395                                         if (current_level < desired_level) {
 396                                                 break;
 397                                         }
 398
 399                                         if (current_level > desired_level) {
 400                                                 page_op = PAGE_OP_FREE;
 401
 402                                                 get_percent_free(&current_percent);
 403
 404                                                 if (stabilized_percentage > current_percent) {
 405                                                         pages_to_process = ((stabilized_percentage - current_percent) * phys_pages) / 100;
 406
 407                                                         if (previous_page_op != page_op) {
 408                                                                 printf("\nCMD: %s pages to go from %d to %d level", (page_op == PAGE_OP_ALLOC) ? "Allocating" : "Freeing", current_level, desired_level);
 409                                                                 previous_page_op = page_op;
 410                                                                 fflush(stdout);
 411                                                         } else {
 412                                                                 printf(".");
 413                                                                 fflush(stdout);
 414                                                         }
 415
 416                                                         if (print_vm_stats_on_page_processing == TRUE) {
 417                                                                 print_vm_statistics();
 418                                                         }
 419                                                         process_pages(pages_to_process, page_op);
 420                                                         ok_to_print_stablity_message = TRUE;
 421                                                 }
 422                                         }
 423
 424                                         while (current_level == desired_level) {
 425                                                 get_percent_free(&current_percent);
 426                                                 if (ok_to_print_stablity_message == TRUE) {
 427                                                         print_vm_statistics();
 428                                                         printf("\nStabilizing at Percent: %d Level: %d", current_percent, current_level);
 429                                                         fflush(stdout);
 430                                                         ok_to_print_stablity_message = FALSE;
 431                                                         previous_page_op = 0;
 432                                                 } else {
 433                                                         printf(".");
 434                                                         fflush(stdout);
 435                                                 }
 436
 437                                                 stabilized_percentage = current_percent;
 438                                                 sleep(sleep_seconds);
 439                                                 current_level =  read_sysctl_int("kern.memorystatus_vm_pressure_level");
 440                                         }
 441                                 }
 442                         }
 443
 444                         get_percent_free(&current_percent);
 445                         //printf("Percent: %d Level: %d\n", current_percent, current_level);
 446                         sleep(1);
 447
 448                         if (print_vm_stats) {
 449                                 print_vm_stats_on_page_processing = TRUE;
 450                         }
 451
 452         } /* while */
 453 }
 454
 455 void
 456 munch_for_percentage(unsigned int sleep_seconds, unsigned int wait_percent_free, unsigned int print_vm_stats)
 457 {
 458
 459         int             total_pages_allocated = 0;
 460         unsigned int    current_percent = 0;
 461         boolean_t       page_op = PAGE_OP_FREE;
 462         unsigned int    pages_to_process = 0;
 463         boolean_t       print_vm_stats_on_page_processing = FALSE;
 464         boolean_t       previous_page_op = 0;
 465         boolean_t       ok_to_print_stablity_message = TRUE;
 466
 467         /* Allocate until memory level is hit. */
 468
 469         get_percent_free(&current_percent);
 470
 471         /*
 472          * "wait" mode doesn't alloc, it just waits and exits.  This is used
 473          * while waiting for *other* processes to allocate memory.
 474          */
 475         if (wait_percent_free) {
 476                 while (current_percent > wait_percent_free) {
 477                         sleep(sleep_seconds);
 478                         get_percent_free (&current_percent);
 479                 }
 480                 return;
 481         }
 482
 483         page_op = PAGE_OP_ALLOC;
 484         previous_page_op = 0;
 485
 486         while (1) {
 487
 488                 if (current_percent > desired_percent) {
 489                         pages_to_process = ((current_percent - desired_percent) * phys_pages) / 100;
 490                         page_op = PAGE_OP_ALLOC;
 491                 } else {
 492                         pages_to_process = ((desired_percent - current_percent) * phys_pages) / 100;
 493                         page_op = PAGE_OP_FREE;
 494                 }
 495
 496                 if (pages_to_process > 0) {
 497
 498                         if (page_op != previous_page_op) {
 499                                 //printf("\n%s %d pages to go from %d%% to %d%% pages free\n", (page_op == PAGE_OP_ALLOC) ? "Allocating" : "Freeing", pages_to_process, current_percent, desired_percent);
 500                                 printf("\nCMD: %s pages to go from %d%% to %d%% percent free", (page_op == PAGE_OP_ALLOC) ? "Allocating" : "Freeing", current_percent, desired_percent);
 501                                 fflush(stdout);
 502                                 previous_page_op = page_op;
 503                         } else {
 504                                 printf(".");
 505                                 fflush(stdout);
 506                         }
 507
 508                         if (page_op == PAGE_OP_ALLOC) {
 509                                 total_pages_allocated += pages_to_process;
 510                                 process_pages(pages_to_process, page_op);
 511                                 ok_to_print_stablity_message = TRUE;
 512                         } else {
 513
 514                                 if (total_pages_allocated >= pages_to_process) {
 515                                         total_pages_allocated -= pages_to_process;
 516                                         process_pages(pages_to_process, page_op);
 517                                         ok_to_print_stablity_message = TRUE;
 518                                 } else {
 519                                         get_percent_free(&current_percent);
 520                                         if (ok_to_print_stablity_message == TRUE) {
 521                                                 printf("\nDesired Percent: %d, Current Percent: %d. No pages to free so waiting", desired_percent, current_percent);
 522                                                 fflush(stdout);
 523                                                 ok_to_print_stablity_message = FALSE;
 524                                         }
 525                                 }
 526                         }
 527
 528                         //printf("kernel memorystatus: %d%% free, allocated %d pages total. Requested: %d\n", current_percent, total_pages_allocated, desired_percent);
 529                         if (print_vm_stats) {
 530                                 print_vm_stats_on_page_processing = TRUE;
 531                         }
 532                 } else {
 533                         if (ok_to_print_stablity_message == TRUE) {
 534                                 print_vm_statistics();
 535                                 printf("\nStable at percent free: %d", current_percent);
 536                                 fflush(stdout);
 537                                 ok_to_print_stablity_message = FALSE;
 538                         } else {
 539                                 printf(".");
 540                                 fflush(stdout);
 541                         }
 542                         print_vm_stats_on_page_processing = FALSE;
 543                 }
 544
 545                 if (print_vm_stats_on_page_processing) {
 546
 547                         print_vm_statistics();
 548
 549                         if (print_vm_stats_on_page_processing == TRUE) {
 550                                 print_vm_stats_on_page_processing = FALSE;
 551                         }
 552                 }
 553
 554                 sleep(sleep_seconds);
 555
 556                 get_percent_free(&current_percent);
 557         } /* while */
 558 }
 559
 560 int
 561 main(int argc, char * const argv[])
 562 {
 563         int opt;
 564         unsigned int wait_percent_free = 0;
 565         unsigned int current_percent = 0;
 566         unsigned int print_vm_stats = 0;
 567         char         level[10];
 568
 569         while ((opt = getopt(argc, argv, "hl:p:s:w:vQS")) != -1) {
 570                 switch (opt) {
 571                         case 'h':
 572                                 usage();
 573                                 break;
 574                         case 'l':
 575                                 strlcpy(level, optarg, 9);
 576
 577                                 if (strncasecmp(level, "normal", 6) == 0) {
 578                                         desired_level = DISPATCH_MEMORYPRESSURE_NORMAL;
 579                                         percent_for_level = 90;
 580                                 } else if (strncasecmp(level, "warn", 4) == 0) {
 581                                         desired_level = DISPATCH_MEMORYPRESSURE_WARN;
 582                                         percent_for_level = 60;
 583
 584                                 } else if (strncasecmp(level, "critical", 8) == 0) {
 585                                         desired_level = DISPATCH_MEMORYPRESSURE_CRITICAL;
 586                                         percent_for_level = 30;
 587
 588                                 } else {
 589                                         printf("Incorrect level. Allowed \"normal\" or \"warn\" or \"critical\". Specified: %s\n", level);
 590                                         exit(0);
 591                                 }
 592                                 break;
 593                         case 'p':
 594                                 desired_percent = atoi(optarg);
 595                                 break;
 596                         case 's':
 597                                 sleep_seconds = atoi(optarg);
 598                                 break;
 599                         case 'w':
 600                                 wait_percent_free = atoi(optarg);
 601                                 break;
 602                         case 'v':
 603                                 print_vm_stats = 1;
 604                                 break;
 605                         case 'Q':
 606                                 quiet_mode_on = TRUE;
 607                                 break;
 608                         case 'S':
 609                                 simulate_mode_on = TRUE;
 610                                 break;
 611                         default:
 612                                 usage();
 613                 }
 614         }
 615
 616         if (simulate_mode_on == TRUE && desired_level == 0) {
 617                 printf("Expected level with -l along with \"simulated\" mode.\n");
 618                 return 0;
 619         }
 620
 621         phys_mem   = read_sysctl_int("hw.physmem");
 622         phys_pages = (unsigned int) (phys_mem / PAGE_SIZE);
 623
 624         printf("The system has %lu (%d pages with a page size of %d).\n", phys_mem, phys_pages, PAGE_SIZE);
 625
 626         print_vm_statistics();
 627
 628         get_percent_free(&current_percent);
 629         printf("System-wide memory free percentage: %d%%\n", current_percent);
 630
 631         if (desired_percent == 0 && wait_percent_free == 0 && desired_level == 0) {
 632                 return 0;
 633         }
 634
 635         if (simulate_mode_on == TRUE) {
 636
 637                 /*
 638                         We use the sysctl "kern.memorypressure_manual_trigger" for this mode. Here's a blurb:
 639
 640                         Supported behaviors when using the manual trigger tests.
 641
 642                         #define TEST_LOW_MEMORY_TRIGGER_ONE             1       most suitable app is notified
 643                         #define TEST_LOW_MEMORY_TRIGGER_ALL             2       all apps are notified
 644                         #define TEST_PURGEABLE_TRIGGER_ONE              3
 645                         #define TEST_PURGEABLE_TRIGGER_ALL              4
 646                         #define TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ONE   5
 647                         #define TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ALL   6
 648
 649                         So, for example, to simulate one app getting a poke when the "pressure" reaches critical levels: "sudo sysctl -w kern.memorypressure_manual_trigger = level"
 650                         where level is calculated as: ((TEST_LOW_MEMORY_TRIGGER_ONE << 16) | NOTE_MEMORYSTATUS_PRESSURE_CRITICAL), which will be "65540".
 651
 652                         For this tool, currently, we only support the "TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ALL" options.
 653                 */
 654
 655 #define TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ALL   6
 656
 657                 unsigned int var = 0;
 658                 size_t var_size = 0;
 659                 int error = 0;
 660
 661                 var_size = sizeof(var);
 662
 663                 var = ((TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ALL << 16) | desired_level);
 664
 665                 error = sysctlbyname("kern.memorypressure_manual_trigger", NULL, 0, &var, var_size);
 666
 667                 if(error) {
 668                         perror("sysctl: kern.memorypressure_manual_trigger failed ");
 669                         exit(-1);
 670                 }
 671
 672                 printf("Waiting %d seconds before resetting system state\n", sleep_seconds);
 673
 674                 sleep(sleep_seconds);
 675
 676                 var_size = sizeof(var);
 677
 678                 var = ((TEST_LOW_MEMORY_PURGEABLE_TRIGGER_ALL << 16) | DISPATCH_MEMORYPRESSURE_NORMAL);
 679
 680                 error = sysctlbyname("kern.memorypressure_manual_trigger", NULL, 0, &var, var_size);
 681
 682                 if(error) {
 683                         perror("sysctl: kern.memorypressure_manual_trigger failed ");
 684                         exit(-1);
 685                 }
 686
 687                 printf("Reset system state\n");
 688
 689         } else {
 690                 range_start_addr = mmap(NULL, MAX_RANGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, 0);
 691
 692                 if (range_start_addr == MAP_FAILED) {
 693                         perror("mmap failed");
 694                 } else {
 695
 696                         int             error = 0;
 697                         pthread_t       thread = NULL;
 698
 699                         error = pthread_create(&thread, NULL, (void*) reference_pages, NULL);
 700
 701                         range_current_addr = range_start_addr;
 702                         range_end_addr = range_start_addr + MAX_RANGE_SIZE;
 703                         start_allocing_pages = 1;
 704
 705                         if (desired_level) {
 706                                 tool_mode = TOOL_MODE_FOR_LEVEL;
 707                                 munch_for_level(sleep_seconds, print_vm_stats);
 708                         } else {
 709                                 tool_mode = TOOL_MODE_FOR_PERCENT;
 710                                 munch_for_percentage(sleep_seconds, wait_percent_free, print_vm_stats);
 711                         }
 712                 }
 713         }
 714
 715         return 0;
 716 }