home *** CD-ROM | disk | FTP | other *** search
- /*
- * Random page access benchmark.
- */
- #include <sys/vadvise.h>
-
- char *valloc();
- int rand();
-
- main(argc, argv)
- char *argv[];
- {
- register int npages = 4096, pagesize, pn, i, niter;
- int vflag = 0, debug = 0;
- char *pages, *name;
-
- name = argv[0];
- argc--, argv++;
- again:
- if (argc < 1) {
- usage:
- printf("usage: %s [ -d ] [ -v ] [ -p #pages ] niter\n", name);
- exit(1);
- }
- if (strcmp(*argv, "-p") == 0) {
- argc--, argv++;
- if (argc < 1)
- goto usage;
- npages = atoi(*argv);
- if (npages <= 0) {
- printf("%s: Bad page count.\n", *argv);
- exit(2);
- }
- argc--, argv++;
- goto again;
- }
- if (strcmp(*argv, "-v") == 0) {
- argc--, argv++;
- vflag++;
- goto again;
- }
- if (strcmp(*argv, "-d") == 0) {
- argc--, argv++;
- debug++;
- goto again;
- }
- niter = atoi(*argv);
- pagesize = getpagesize();
- pages = valloc(npages * pagesize);
- if (pages == (char *)0) {
- printf("Can't allocate %d pages (%2.1f megabytes).\n",
- npages, (npages * pagesize) / (1024. * 1024.));
- exit(3);
- }
- if (vflag)
- vadvise(VA_ANOM);
- for (i = 0; i < niter; i++) {
- pn = random() % npages;
- if (debug)
- printf("touch page %d\n", pn);
- pages[pagesize * pn] = 1;
- }
- }
-