[PATCH] Include io depth distribution statistics

Calculate the distribution of io depths for the job run.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/HOWTO b/HOWTO
index 40f974cba7fdfce741c3ca641ef9975c8cd9b61c..95d059e766e6399f29d8097331a076db4df29161 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -539,6 +539,7 @@ Client1 (g=0): err= 0:
     clat (msec): min=    0, max=  631, avg=48.50, stdev=86.82
     bw (KiB/s) : min=    0, max= 1196, per=51.00%, avg=664.02, stdev=681.68
   cpu        : usr=1.49%, sys=0.25%, ctx=7969
+  IO depths    : 1=0.1%, 2=0.3%, 4=0.5%, 8=99.0%, 16=0.0%, 32=0.0%, >32=0.0%
 
 The client number is printed, along with the group id and error of that
 thread. Below is the io statistics, here for writes. In the order listed,
@@ -563,6 +564,11 @@ runt=              The runtime of that thread
                same disk, since they are then competing for disk access.
 cpu=           CPU usage. User and system time, along with the number
                of context switches this thread went through.
+IO depths=     The distribution of io depths over the job life time. The
+               numbers are divided into powers of 2, so for example the
+               16= entries includes depths up to that value but higher
+               than the previous entry. In other words, it covers the
+               range from 16 to 31.
 
 After each client has been listed, the group statistics are printed. They
 will look like this:

diff --git a/fio.h b/fio.h
index e85d6cc1f0ac2011fb79780adb838039cd8b56a0..c21440667a51bf6c09db8c39b799901dbdf97446 100644 (file)
--- a/fio.h
+++ b/fio.h
@@ -167,6 +167,11 @@ struct fio_file {
        unsigned int unlink;
 };
 
+/*
+ * How many depth levels to log
+ */
+#define FIO_IO_U_MAP_NR        8
+
 /*
  * This describes a single thread/process executing a fio job.
  */
@@ -264,6 +269,8 @@ struct thread_data {
         * Current IO depth and list of free and busy io_u's.
         */
        unsigned int cur_depth;
+       unsigned int io_u_map[FIO_IO_U_MAP_NR];
+       unsigned long total_io_u;
        struct list_head io_u_freelist;
        struct list_head io_u_busylist;
 

diff --git a/io_u.c b/io_u.c
index 834e5d214d5da390365858f36d67ed3fd67127a6..5e53b81443cda688bdb42163dc2a5af4cc28fe04 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -227,6 +227,31 @@ static int fill_io_u(struct thread_data *td, struct fio_file *f,
        return 1;
 }
 
+static void io_u_mark_depth(struct thread_data *td)
+{
+       int index = 0;
+
+       switch (td->cur_depth) {
+       default:
+               index++;
+       case 32 ... 63:
+               index++;
+       case 16 ... 31:
+               index++;
+       case 8 ... 15:
+               index++;
+       case 4 ... 7:
+               index++;
+       case 2 ... 3:
+               index++;
+       case 1:
+               break;
+       }
+
+       td->io_u_map[index]++;
+       td->total_io_u++;
+}
+
 struct io_u *__get_io_u(struct thread_data *td)
 {
        struct io_u *io_u = NULL;
@@ -240,6 +265,7 @@ struct io_u *__get_io_u(struct thread_data *td)
                list_del(&io_u->list);
                list_add(&io_u->list, &td->io_u_busylist);
                td->cur_depth++;
+               io_u_mark_depth(td);
        }
 
        return io_u;

diff --git a/stat.c b/stat.c
index e7ffd8ccf1f7bc6de8241a2e26b25035d0a8169d..b4806e0e8c48dfb5557be2f4abcdf31bf4ed41e1 100644 (file)
--- a/stat.c
+++ b/stat.c
@@ -375,6 +375,8 @@ static void show_thread_status(struct thread_data *td,
 {
        double usr_cpu, sys_cpu;
        unsigned long runtime;
+       double io_u_dist[FIO_IO_U_MAP_NR];
+       int i;
 
        if (!(td->io_bytes[0] + td->io_bytes[1]) && !td->error)
                return;
@@ -397,6 +399,16 @@ static void show_thread_status(struct thread_data *td,
        }
 
        fprintf(f_out, "  cpu          : usr=%3.2f%%, sys=%3.2f%%, ctx=%lu\n", usr_cpu, sys_cpu, td->ctx);
+
+       /*
+        * Do depth distribution calculations
+        */
+       for (i = 0; i < FIO_IO_U_MAP_NR; i++) {
+               io_u_dist[i] = (double) td->io_u_map[i] / (double) td->total_io_u;
+               io_u_dist[i] *= 100.0;
+       }
+
+       fprintf(f_out, "  IO depths    : 1=%3.1f%%, 2=%3.1f%%, 4=%3.1f%%, 8=%3.1f%%, 16=%3.1f%%, 32=%3.1f%%, >32=%3.1f%%\n", io_u_dist[0], io_u_dist[1], io_u_dist[2], io_u_dist[3], io_u_dist[4], io_u_dist[5], io_u_dist[6]);
 }
 
 static void show_ddir_status_terse(struct thread_data *td,