/* * 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 ] [ -k #Kb ] niter\n", name); exit(1); } if (strcmp(*argv, "-k") == 0) { argc--, argv++; if (argc < 1) goto usage; npages = atoi(*argv); if (npages <= 0) { printf("%s: Bad virtual memory size.\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(); npages /= pagesize / 1024; 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 (pagesize != 1024) printf("Pagesize %dKb\n", pagesize / 1024); 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; } }