Merge branch 'fio-docs-ci' of https://github.com/vincentkfu/fio

[fio.git] / HOWTO.rst

diff --git a/HOWTO.rst b/HOWTO.rst
index db30ed1f8841249e3d7f6aca944aa8688f8122e1..ac1f34787088345dfaaf82a00c5a2fc6f9081752 100644 (file)
--- a/HOWTO.rst
+++ b/HOWTO.rst
@@ -2247,14 +2247,6 @@ with the caveat that when used on the command line, they must come after the
     map and release for each IO. This is more efficient, and reduces the
     IO latency as well.
 
-.. option:: hipri : [io_uring]
-
-    If this option is set, fio will attempt to use polled IO completions.
-    Normal IO completions generate interrupts to signal the completion of
-    IO, polled completions do not. Hence they are require active reaping
-    by the application. The benefits are more efficient IO for high IOPS
-    scenarios, and lower latencies for low queue depth IO.
-
 .. option:: registerfiles : [io_uring]
 
        With this option, fio registers the set of files being used with the
@@ -2275,6 +2267,33 @@ with the caveat that when used on the command line, they must come after the
        When :option:`sqthread_poll` is set, this option provides a way to
        define which CPU should be used for the polling thread.
 
+.. option:: hipri
+
+   [io_uring]
+
+        If this option is set, fio will attempt to use polled IO completions.
+        Normal IO completions generate interrupts to signal the completion of
+        IO, polled completions do not. Hence they are require active reaping
+        by the application. The benefits are more efficient IO for high IOPS
+        scenarios, and lower latencies for low queue depth IO.
+
+   [pvsync2]
+
+       Set RWF_HIPRI on I/O, indicating to the kernel that it's of higher priority
+       than normal.
+
+   [sg]
+
+       If this option is set, fio will attempt to use polled IO completions.
+       This will have a similar effect as (io_uring)hipri. Only SCSI READ and
+       WRITE commands will have the SGV4_FLAG_HIPRI set (not UNMAP (trim) nor
+       VERIFY). Older versions of the Linux sg driver that do not support
+       hipri will simply ignore this flag and do normal IO. The Linux SCSI
+       Low Level Driver (LLD) that "owns" the device also needs to support
+       hipri (also known as iopoll and mq_poll). The MegaRAID driver is an
+       example of a SCSI LLD. Default: clear (0) which does normal
+       (interrupted based) IO.
+
 .. option:: userspace_reap : [libaio]
 
        Normally, with the libaio engine in use, fio will use the
@@ -2283,11 +2302,6 @@ with the caveat that when used on the command line, they must come after the
        reap events. The reaping mode is only enabled when polling for a minimum of
        0 events (e.g. when :option:`iodepth_batch_complete` `=0`).
 
-.. option:: hipri : [pvsync2]
-
-       Set RWF_HIPRI on I/O, indicating to the kernel that it's of higher priority
-       than normal.
-
 .. option:: hipri_percentage : [pvsync2]
 
        When hipri is set this determines the probability of a pvsync2 I/O being high
@@ -2490,11 +2504,17 @@ with the caveat that when used on the command line, they must come after the
 
        Specify the label or UUID of the DAOS container to open.
 
-.. option:: chunk_size=int : [dfs]
+.. option:: chunk_size=int
+
+   [dfs]
 
        Specificy a different chunk size (in bytes) for the dfs file.
        Use DAOS container's chunk size by default.
 
+   [libhdfs]
+
+       The size of the chunk to use for each file.
+
 .. option:: object_class=str : [dfs]
 
        Specificy a different object class for the dfs file.
@@ -2508,10 +2528,6 @@ with the caveat that when used on the command line, they must come after the
 
        libhdfs will create chunk in this HDFS directory.
 
-.. option:: chunk_size : [libhdfs]
-
-       The size of the chunk to use for each file.
-
 .. option:: verb=str : [rdma]
 
        The RDMA verb to use on this side of the RDMA ioengine connection. Valid
@@ -2597,18 +2613,6 @@ with the caveat that when used on the command line, they must come after the
        a valid stream identifier) fio will open a stream and then close it when done. Default
        is 0.
 
-.. option:: hipri : [sg]
-
-       If this option is set, fio will attempt to use polled IO completions.
-       This will have a similar effect as (io_uring)hipri. Only SCSI READ and
-       WRITE commands will have the SGV4_FLAG_HIPRI set (not UNMAP (trim) nor
-       VERIFY). Older versions of the Linux sg driver that do not support
-       hipri will simply ignore this flag and do normal IO. The Linux SCSI
-       Low Level Driver (LLD) that "owns" the device also needs to support
-       hipri (also known as iopoll and mq_poll). The MegaRAID driver is an
-       example of a SCSI LLD. Default: clear (0) which does normal
-       (interrupted based) IO.
-
 .. option:: http_host=str : [http]
 
        Hostname to connect to. For S3, this could be the bucket hostname.