Add support for randomness of any IO direction
sequential_random used to be applied to all of the IO
directions, with no possibility of having different settings
for reads, writes, and trims. Now it supports setting each of
them individually.
By default, if you do:
sequential_random=50
it will still apply to all three. If you do:
sequential_random=10,90,80
you would get reads 10% random, writes 90% random, and trims
80% random.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/HOWTO b/HOWTO
index a2de470..8768b99 100644
--- a/HOWTO
+++ b/HOWTO
@@ -443,9 +443,11 @@
can be given for both read and writes. If a single int is
given, it will apply to both. If a second int is specified
after a comma, it will apply to writes only. In other words,
- the format is either bs=read_and_write or bs=read,write.
- bs=4k,8k will thus use 4k blocks for reads, and 8k blocks
- for writes. If you only wish to set the write size, you
+ the format is either bs=read_and_write or bs=read,write,trim.
+ bs=4k,8k will thus use 4k blocks for reads, 8k blocks for
+ writes, and 8k for trims. You can terminate the list with
+ a trailing comma. bs=4k,8k, would use the default value for
+ trims.. If you only wish to set the write size, you
can do so by passing an empty read size - bs=,8k will set
8k for writes and leave the read default value.
@@ -773,12 +775,10 @@
is fully random. It can be set from anywhere from 0 to 100.
Setting it to 0 would make the workload fully sequential. Any
setting in between will result in a random mix of sequential
- and random IO, at the given percentages.
+ and random IO, at the given percentages. It is possible to
+ set different values for reads, writes, and trim. To do so,
+ simply use a comma separated list. See blocksize.
-percentage_sequential=int See percentage_random. It is guaranteed that
- they add up to 100. The later setting has priority, each
- will adjust the other.
-
norandommap Normally fio will cover every block of the file when doing
random IO. If this option is given, fio will just get a
new random offset without looking at past io history. This