Add support for modifying the randomness of a workload
Fio supports random or sequential IO, or random IO with a number of
sequential IOs in between. The percentage_random options allows
more fine grained control over this. It defaults to 100, which would
make any random workload still purely random. If set below 100,
there will be some percentage of sequential IOs. This happens randomly,
but at the specified percentages.
The percentage_sequential option is just the complement of that, it
is guaranteed that:
percentage_sequential + percentage_random == 100%
The later setting has priority, each will adjust the other.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fio.1 b/fio.1
index 401d956..5082bf8 100644
--- a/fio.1
+++ b/fio.1
@@ -641,6 +641,15 @@
random_distribution=zipf:1.2 as the option. If a non-uniform model is used,
fio will disable use of the random map.
.TP
+.BI percentage_random \fR=\fPint
+For a random workload, set how big a percentage should be random. This defaults
+to 100%, in which case the workload is fully random. It can be set from
+anywhere from 0 to 100. Setting it to 0 would make the workload fully
+sequential.
+.TP
+.BI percentage_sequential \fR=\fPint
+See \fBpercentage_random\fR.
+.TP
.B norandommap
Normally \fBfio\fR will cover every block of the file when doing random I/O. If
this parameter is given, a new offset will be chosen without looking at past