Add support for mixing a random IO workload a bit

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 76613714a14a063b4adc3133ee954f2b966748aa..051a4554a95ff8a1229d3154a1c6bd31f701c9c6 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -228,7 +228,14 @@ rw=str             Type of io pattern. Accepted values are:
 
                For the mixed io types, the default is to split them 50/50.
                For certain types of io the result may still be skewed a bit,
-               since the speed may be different.
+               since the speed may be different. It is possible to specify
+               a number of IO's to do before getting a new offset - this
+               is only useful for random IO, where fio would normally
+               generate a new random offset for every IO. If you append
+               eg 8 to randread, you would get a new random offset for
+               every 8 IO's. The result would be a seek for only every 8
+               IO's, instead of for every IO. Use rw=randread:8 to specify
+               that.
 
 randrepeat=bool        For random IO workloads, seed the generator in a predictable
                way so that results are repeatable across repetitions.