From: Pankaj Raghav <p.raghav@samsung.com>
Date: Fri, 7 Oct 2022 12:05:28 +0000 (+0200)
Subject: examples: uring-cmd-zoned: expand the reasoning behind QD1
X-Git-Tag: fio-3.33~19
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=b19c5ee1357ffb74f4de57b1617364bbbaacf1a0;p=fio.git

examples: uring-cmd-zoned: expand the reasoning behind QD1

Expand the reasoning behind using QD1 for zoned devices with io_uring_cmd
engine.

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Vincent Fu <vincent.fu@samsung.com>
---

diff --git a/examples/uring-cmd-zoned.fio b/examples/uring-cmd-zoned.fio
index 58e8f79e..89be61be 100644
--- a/examples/uring-cmd-zoned.fio
+++ b/examples/uring-cmd-zoned.fio
@@ -1,7 +1,11 @@
 # io_uring_cmd I/O engine for nvme-ns generic zoned character device
 #
-# NOTE: with write workload iodepth must be set to 1 as there is no IO
-# scheduler.
+# NOTE:
+# Regular writes against a zone should be limited to QD1, as the device can
+# reorder the requests.
+#
+# As the passthrough path do not use an IO scheduler (such as mq-deadline),
+# the queue depth should be limited to 1 to avoid zone invalid writes.
 
 [global]
 filename=/dev/ng0n1