the next. Multiple files can still be
open depending on 'openfiles'.
- The string can have a number appended, indicating how
- often to switch to a new file. So if option random:4 is
- given, fio will switch to a new random file after 4 ios
- have been issued.
+ zipf Use a zipfian distribution to decide what file
+ to access.
+
+ pareto Use a pareto distribution to decide what file
+ to access.
+
+ gauss Use a gaussian (normal) distribution to decide
+ what file to access.
+
+ For random, roundrobin, and sequential, a postfix can be
+ appended to tell fio how many I/Os to issue before switching
+ to a new file. For example, specifying
+ 'file_service_type=random:8' would cause fio to issue 8 I/Os
+ before selecting a new file at random. For the non-uniform
+ distributions, a floating point postfix can be given to
+ influence how the distribution is skewed. See
+ 'random_distribution' for a description of how that would work.
ioengine=str Defines how the job issues io to the file. The following
types are defined:
};
/*
- * roundrobin available files, or choose one at random, or do each one
- * serially.
+ * How fio chooses what file to service next. Choice of uniformly random, or
+ * some skewed random variants, or just sequentially go through them or
+ * roundrobing.
*/
enum {
- FIO_FSERVICE_RANDOM = 1,
- FIO_FSERVICE_RR = 2,
- FIO_FSERVICE_SEQ = 3,
+ FIO_FSERVICE_RANDOM = 1,
+ FIO_FSERVICE_RR = 2,
+ FIO_FSERVICE_SEQ = 3,
+ __FIO_FSERVICE_NONUNIFORM = 0x100,
+ FIO_FSERVICE_ZIPF = __FIO_FSERVICE_NONUNIFORM | 4,
+ FIO_FSERVICE_PARETO = __FIO_FSERVICE_NONUNIFORM | 5,
+ FIO_FSERVICE_GAUSS = __FIO_FSERVICE_NONUNIFORM | 6,
+
+ FIO_FSERVICE_SHIFT = 10,
};
/*
.TP
.B sequential
Do each file in the set sequentially.
+.TP
+.B zipf
+Use a zipfian distribution to decide what file to access.
+.TP
+.B pareto
+Use a pareto distribution to decide what file to access.
+.TP
+.B gauss
+Use a gaussian (normal) distribution to decide what file to access.
.RE
.P
-The number of I/Os to issue before switching to a new file can be specified by
-appending `:\fIint\fR' to the service type.
+For \fBrandom\fR, \fBroundrobin\fR, and \fBsequential\fR, a postfix can be
+appended to tell fio how many I/Os to issue before switching to a new file.
+For example, specifying \fBfile_service_type=random:8\fR would cause fio to
+issue \fI8\fR I/Os before selecting a new file at random. For the non-uniform
+distributions, a floating point postfix can be given to influence how the
+distribution is skewed. See \fBrandom_distribution\fR for a description of how
+that would work.
.RE
.TP
.BI ioengine \fR=\fPstr
unsigned int next_file;
struct frand_state next_file_state;
};
+ union {
+ struct zipf_state next_file_zipf;
+ struct gauss_state next_file_gauss;
+ };
+ union {
+ double zipf_theta;
+ double pareto_h;
+ double gauss_dev;
+ };
int error;
int sig;
int done;
if (td->o.file_service_type == FIO_FSERVICE_RANDOM)
init_rand_seed(&td->next_file_state, td->rand_seeds[FIO_RAND_FILE_OFF], use64);
+ else if (td->o.file_service_type & __FIO_FSERVICE_NONUNIFORM) {
+ unsigned long nranges;
+
+ nranges = td->o.nr_files << FIO_FSERVICE_SHIFT;
+
+ if (td->o.file_service_type == FIO_FSERVICE_ZIPF) {
+ zipf_init(&td->next_file_zipf, nranges, td->zipf_theta, td->rand_seeds[FIO_RAND_FILE_OFF]);
+ zipf_disable_hash(&td->next_file_zipf);
+ } else if (td->o.file_service_type == FIO_FSERVICE_PARETO) {
+ pareto_init(&td->next_file_zipf, nranges, td->pareto_h, td->rand_seeds[FIO_RAND_FILE_OFF]);
+ zipf_disable_hash(&td->next_file_zipf);
+ } else if (td->o.file_service_type == FIO_FSERVICE_GAUSS) {
+ gauss_init(&td->next_file_gauss, nranges, td->gauss_dev, td->rand_seeds[FIO_RAND_FILE_OFF]);
+ gauss_disable_hash(&td->next_file_gauss);
+ }
+ }
init_rand_seed(&td->file_size_state, td->rand_seeds[FIO_RAND_FILE_SIZE_OFF], use64);
init_rand_seed(&td->trim_state, td->rand_seeds[FIO_RAND_TRIM_OFF], use64);
if (!get_next_rand_offset(td, f, ddir, b))
return 0;
- if (td->o.time_based) {
+ if (td->o.time_based ||
+ (td->o.file_service_type & __FIO_FSERVICE_NONUNIFORM)) {
fio_file_reset(td, f);
if (!get_next_rand_offset(td, f, ddir, b))
return 0;
io_u_mark_lat_msec(td, usec / 1000);
}
+static unsigned int __get_next_fileno_rand(struct thread_data *td)
+{
+ unsigned long fileno;
+
+ if (td->o.file_service_type == FIO_FSERVICE_RANDOM) {
+ uint64_t frand_max = rand_max(&td->next_file_state);
+ unsigned long r;
+
+ r = __rand(&td->next_file_state);
+ return (unsigned int) ((double) td->o.nr_files
+ * (r / (frand_max + 1.0)));
+ }
+
+ if (td->o.file_service_type == FIO_FSERVICE_ZIPF)
+ fileno = zipf_next(&td->next_file_zipf);
+ else if (td->o.file_service_type == FIO_FSERVICE_PARETO)
+ fileno = pareto_next(&td->next_file_zipf);
+ else if (td->o.file_service_type == FIO_FSERVICE_GAUSS)
+ fileno = gauss_next(&td->next_file_gauss);
+ else {
+ log_err("fio: bad file service type: %d\n", td->o.file_service_type);
+ assert(0);
+ return 0;
+ }
+
+ return fileno >> FIO_FSERVICE_SHIFT;
+}
+
/*
* Get next file to service by choosing one at random
*/
enum fio_file_flags goodf,
enum fio_file_flags badf)
{
- uint64_t frand_max = rand_max(&td->next_file_state);
struct fio_file *f;
int fno;
do {
int opened = 0;
- unsigned long r;
- r = __rand(&td->next_file_state);
- fno = (unsigned int) ((double) td->o.nr_files
- * (r / (frand_max + 1.0)));
+ fno = __get_next_fileno_rand(td);
f = td->files[fno];
if (fio_file_done(f))
put_file_log(td, f);
td_io_close_file(td, f);
io_u->file = NULL;
- fio_file_set_done(f);
- td->nr_done_files++;
- dprint(FD_FILE, "%s: is done (%d of %d)\n", f->file_name,
+ if (td->o.file_service_type & __FIO_FSERVICE_NONUNIFORM)
+ fio_file_reset(td, f);
+ else {
+ fio_file_set_done(f);
+ td->nr_done_files++;
+ dprint(FD_FILE, "%s: is done (%d of %d)\n", f->file_name,
td->nr_done_files, td->o.nr_files);
+ }
} while (1);
return 0;
static int str_fst_cb(void *data, const char *str)
{
struct thread_data *td = data;
- char *nr = get_opt_postfix(str);
+ double val;
+ bool done = false;
+ char *nr;
td->file_service_nr = 1;
- if (nr) {
- td->file_service_nr = atoi(nr);
+
+ switch (td->o.file_service_type) {
+ case FIO_FSERVICE_RANDOM:
+ case FIO_FSERVICE_RR:
+ case FIO_FSERVICE_SEQ:
+ nr = get_opt_postfix(str);
+ if (nr) {
+ td->file_service_nr = atoi(nr);
+ free(nr);
+ }
+ done = true;
+ break;
+ case FIO_FSERVICE_ZIPF:
+ val = FIO_DEF_ZIPF;
+ break;
+ case FIO_FSERVICE_PARETO:
+ val = FIO_DEF_PARETO;
+ break;
+ case FIO_FSERVICE_GAUSS:
+ val = 0.0;
+ break;
+ default:
+ log_err("fio: bad file service type: %d\n", td->o.file_service_type);
+ return 1;
+ }
+
+ if (done)
+ return 0;
+
+ nr = get_opt_postfix(str);
+ if (nr && !str_to_float(nr, &val, 0)) {
+ log_err("fio: file service type random postfix parsing failed\n");
free(nr);
+ return 1;
+ }
+
+ free(nr);
+
+ switch (td->o.file_service_type) {
+ case FIO_FSERVICE_ZIPF:
+ if (val == 1.00) {
+ log_err("fio: zipf theta must be different than 1.0\n");
+ return 1;
+ }
+ if (parse_dryrun())
+ return 0;
+ td->zipf_theta = val;
+ break;
+ case FIO_FSERVICE_PARETO:
+ if (val <= 0.00 || val >= 1.00) {
+ log_err("fio: pareto input out of range (0 < input < 1.0)\n");
+ return 1;
+ }
+ if (parse_dryrun())
+ return 0;
+ td->pareto_h = val;
+ break;
+ case FIO_FSERVICE_GAUSS:
+ if (val < 0.00 || val >= 100.00) {
+ log_err("fio: normal deviation out of range (0 < input < 100.0 )\n");
+ return 1;
+ }
+ if (parse_dryrun())
+ return 0;
+ td->gauss_dev = val;
+ break;
}
return 0;
.posval = {
{ .ival = "random",
.oval = FIO_FSERVICE_RANDOM,
- .help = "Choose a file at random",
+ .help = "Choose a file at random (uniform)",
+ },
+ { .ival = "zipf",
+ .oval = FIO_FSERVICE_ZIPF,
+ .help = "Zipf randomized",
+ },
+ { .ival = "pareto",
+ .oval = FIO_FSERVICE_PARETO,
+ .help = "Pareto randomized",
+ },
+ { .ival = "gauss",
+ .oval = FIO_FSERVICE_GAUSS,
+ .help = "Normal (guassian) distribution",
},
{ .ival = "roundrobin",
.oval = FIO_FSERVICE_RR,