docs: explain type of memory allocated by md_per_io_size

Note that md_per_io_size always uses malloc for io_uring_cmd.

Signed-off-by: Vincent Fu <vincent.fu@samsung.com>

diff --git a/HOWTO.rst b/HOWTO.rst
index 2a57f60a2b26fdf6eff59cd11a0d579dd7323636..504a64b8082adebdb23b6923509e6042f156cb36 100644 (file)
--- a/HOWTO.rst
+++ b/HOWTO.rst
@@ -2591,7 +2591,9 @@ with the caveat that when used on the command line, they must come after the
 
 .. option:: md_per_io_size=int : [io_uring_cmd] [xnvme]
 
-       Size in bytes for separate metadata buffer per IO. Default: 0.
+        Size in bytes for separate metadata buffer per IO. For io_uring_cmd
+        these buffers are allocated using malloc regardless of what is set for
+        :option:`iomem`. Default: 0.
 
 .. option:: pi_act=int : [io_uring_cmd] [xnvme]
 

diff --git a/fio.1 b/fio.1
index 53fb784964aef8b081a5527738ae2748d94ed7c9..3c5f02b35d454cd5d33275dbfa8b4475ece11f4b 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -2361,7 +2361,9 @@ this option is specified, the option \fBplids\fP or \fBfdp_pli\fP will be ignore
 .RE
 .TP
 .BI (io_uring_cmd,xnvme)md_per_io_size \fR=\fPint
-Size in bytes for separate metadata buffer per IO. Default: 0.
+Size in bytes for separate metadata buffer per IO. For io_uring_cmd these
+buffers are allocated using malloc regardless of what is set for \fBiomem\fR.
+Default: 0.
 .TP
 .BI (io_uring_cmd,xnvme)pi_act \fR=\fPint
 Action to take when nvme namespace is formatted with protection information.