Document file_service_type option

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index de4b0a9932b43f207260a569a5e33349efebc63b..06408e40e16a91fadeea2dce399efc444845b6e5 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -253,6 +253,14 @@ bs_unaligned       If this option is given, any byte size value within bsrange
 
 nrfiles=int    Number of files to use for this job. Defaults to 1.
 
+file_service_type=str  Defines how fio decides which file from a job to
+               service next. The following types are defined:
+
+                       random  Just choose a file at random.
+
+                       roundrobin  Round robin over open files. This
+                               is the default.
+
 ioengine=str   Defines how the job issues io to the file. The following
                types are defined:
 
@@ -289,6 +297,11 @@ ioengine=str       Defines how the job issues io to the file. The following
                                or receive, if the latter only the port
                                argument is used.
 
+                       external Prefix to specify loading an external
+                               IO engine object file. Append the engine
+                               filename, eg ioengine=external:/tmp/foo.o
+                               to load ioengine foo.o in /tmp.
+
 iodepth=int    This defines how many io units to keep in flight against
                the file. The default is 1 for each file defined in this
                job, can be overridden with a larger value for higher