Add Documentation for z unit

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 889526d921393c5a9cc94e099f41283316e4f9ec..177310f64f527ae32e94ac55a32c24e75b48ba99 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -544,6 +544,9 @@ Parameter types
                * *Ti* -- means tebi (Ti) or 1024**4
                * *Pi* -- means pebi (Pi) or 1024**5
 
+       For Zone Block Device Mode:
+               * *z*  -- means Zone
+
        With :option:`kb_base`\=1024 (the default), the unit prefixes are opposite
        from those specified in the SI and IEC 80000-13 standards to provide
        compatibility with old scripts.  For example, 4k means 4096.
@@ -1277,13 +1280,14 @@ I/O type
 .. option:: offset=int
 
        Start I/O at the provided offset in the file, given as either a fixed size in
-       bytes or a percentage. If a percentage is given, the generated offset will be
+       bytes, zones or a percentage. If a percentage is given, the generated offset will be
        aligned to the minimum ``blocksize`` or to the value of ``offset_align`` if
        provided. Data before the given offset will not be touched. This
        effectively caps the file size at `real_size - offset`. Can be combined with
        :option:`size` to constrain the start and end range of the I/O workload.
        A percentage can be specified by a number between 1 and 100 followed by '%',
-       for example, ``offset=20%`` to specify 20%.
+       for example, ``offset=20%`` to specify 20%. In ZBD mode, value can be set as 
+        number of zones using 'z'.
 
 .. option:: offset_align=int
 
@@ -1300,7 +1304,8 @@ I/O type
        intended to operate on a file in parallel disjoint segments, with even
        spacing between the starting points. Percentages can be used for this option.
        If a percentage is given, the generated offset will be aligned to the minimum
-       ``blocksize`` or to the value of ``offset_align`` if provided.
+       ``blocksize`` or to the value of ``offset_align`` if provided. In ZBD mode, value can
+        also be set as number of zones using 'z'.
 
 .. option:: number_ios=int
 
@@ -1818,7 +1823,8 @@ I/O size
        If this option is not specified, fio will use the full size of the given
        files or devices.  If the files do not exist, size must be given. It is also
        possible to give size as a percentage between 1 and 100. If ``size=20%`` is
-       given, fio will use 20% of the full size of the given files or devices.
+       given, fio will use 20% of the full size of the given files or devices. 
+       In ZBD mode, value can also be set as number of zones using 'z'.
        Can be combined with :option:`offset` to constrain the start and end range
        that I/O will be done within.