Add sample zipf distribution randomizer

[fio.git] / options.c

diff --git a/options.c b/options.c
index 380df36afd29f527d33d3949930ebe5f33d676a9..05a6a5081fa576810c9071506e634077ec27a401 100644 (file)
--- a/options.c
+++ b/options.c
@@ -728,6 +728,29 @@ static int str_sfr_cb(void *data, const char *str)
 }
 #endif
 
+static int str_random_distribution_cb(void *data, const char *str)
+{
+       struct thread_data *td = data;
+       double val;
+       char *nr;
+
+       if (td->o.random_distribution == FIO_RAND_DIST_RANDOM)
+               return 0;
+
+       nr = get_opt_postfix(str);
+       if (!nr)
+               val = 0.6;
+       else if (!str_to_float(nr, &val)) {
+               log_err("fio: random postfix parsing failed\n");
+               free(nr);
+               return 1;
+       }
+
+       td->o.zipf_theta = val;
+       free(nr);
+       return 0;
+}
+
 static int check_dir(struct thread_data *td, char *fname)
 {
 #if 0
@@ -1472,6 +1495,24 @@ static struct fio_option options[FIO_MAX_OPTS] = {
                .parent = "norandommap",
                .def    = "0",
        },
+       {
+               .name   = "random_distribution",
+               .type   = FIO_OPT_STR,
+               .off1   = td_var_offset(random_distribution),
+               .cb     = str_random_distribution_cb,
+               .help   = "Random offset distribution generator",
+               .def    = "random",
+               .posval = {
+                         { .ival = "random",
+                           .oval = FIO_RAND_DIST_RANDOM,
+                           .help = "Completely random",
+                         },
+                         { .ival = "zipf",
+                           .oval = FIO_RAND_DIST_ZIPF,
+                           .help = "Zipf distribution",
+                         },
+               },
+       },
        {
                .name   = "nrfiles",
                .alias  = "nr_files",