options: improvements to parse dry run

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 6d80360574e0c89899756cbc6a1d9838293c9c81..e2a4b158dee1c8cc339a9e7edfef814e4728d87e 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -10,6 +10,7 @@ Table of contents
 7. Terse output
 8. Trace file format
 9. CPU idleness profiling
+10. Verification and triggers
 
 1.0 Overview and history
 ------------------------
@@ -962,6 +963,8 @@ random_distribution=str:float       By default, fio will use a completely uniform
                random          Uniform random distribution
                zipf            Zipf distribution
                pareto          Pareto distribution
+               gauss           Normal (guassian) distribution
+               zoned           Zoned random distribution
 
                When using a zipf or pareto distribution, an input value
                is also needed to define the access pattern. For zipf, this
@@ -970,7 +973,28 @@ random_distribution=str:float      By default, fio will use a completely uniform
                what the given input values will yield in terms of hit rates.
                If you wanted to use zipf with a theta of 1.2, you would use
                random_distribution=zipf:1.2 as the option. If a non-uniform
-               model is used, fio will disable use of the random map.
+               model is used, fio will disable use of the random map. For
+               the gauss distribution, a normal deviation is supplied as
+               a value between 0 and 100.
+
+               For a zoned distribution, fio supports specifying percentages
+               of IO access that should fall within what range of the file or
+               device. For example, given a criteria of:
+
+                       60% of accesses should be to the first 10%
+                       30% of accesses should be to the next 20%
+                       8% of accesses should be to to the next 30%
+                       2% of accesses should be to the next 40%
+
+               we can define that through zoning of the random accesses. For
+               the above example, the user would do:
+
+                       random_distribution=zoned:60/10:30/20:8/30:2/40
+
+               similarly to how bssplit works for setting ranges and
+               percentages of block sizes. Like bssplit, it's possible to
+               specify separate zones for reads, writes, and trims. If just
+               one set is given, it'll apply to all of them.
 
 percentage_random=int  For a random workload, set how big a percentage should
                be random. This defaults to 100%, in which case the workload
@@ -1783,6 +1807,9 @@ that defines them is selected.
                enabled when polling for a minimum of 0 events (eg when
                iodepth_batch_complete=0).
 
+[psyncv2] hipri                Set RWF_HIPRI on IO, indicating to the kernel that
+                       it's of higher priority than normal.
+
 [cpu] cpuload=int Attempt to use the specified percentage of CPU cycles.
 
 [cpu] cpuchunks=int Split the load into cycles of the given time. In
@@ -2219,7 +2246,7 @@ localbox$ fio --client=server --trigger-file=/tmp/my-trigger --trigger="ipmi-reb
 For this case, fio would wait for the server to send us the write state,
 then execute 'ipmi-reboot server' when that happened.
 
-10.1 Loading verify state
+10.2 Loading verify state
 -------------------------
 To load store write state, read verification job file must contain
 the verify_state_load option. If that is set, fio will load the previously