From: Max Reitz <mreitz@redhat.com>
To: qemu-block@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>,
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>,
qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>,
Willian Rampazzo <wrampazz@redhat.com>
Subject: [PATCH v5 08/10] iotests/129: Limit mirror job's buffer size
Date: Mon, 18 Jan 2021 11:57:18 +0100 [thread overview]
Message-ID: <20210118105720.14824-9-mreitz@redhat.com> (raw)
In-Reply-To: <20210118105720.14824-1-mreitz@redhat.com>
Issuing 'stop' on the VM drains all nodes. If the mirror job has many
large requests in flight, this may lead to significant I/O that looks a
bit like 'stop' would make the job try to complete (which is what 129
should verify not to happen).
We can limit the I/O in flight by limiting the buffer size, so mirror
will make very little progress during the 'stop' drain.
(We do not need to do anything about commit, which has a buffer size of
512 kB by default; or backup, which goes cluster by cluster. Once we
have asynchronous requests for backup, that will change, but then we can
fine-tune the backup job to only perform a single request on a very
small chunk, too.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
---
tests/qemu-iotests/129 | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tests/qemu-iotests/129 b/tests/qemu-iotests/129
index 104be6dded..80a5db521b 100755
--- a/tests/qemu-iotests/129
+++ b/tests/qemu-iotests/129
@@ -67,7 +67,7 @@ class TestStopWithBlockJob(iotests.QMPTestCase):
def test_drive_mirror(self):
self.do_test_stop("drive-mirror", device="drive0",
target=self.target_img, format=iotests.imgfmt,
- sync="full")
+ sync="full", buf_size=65536)
def test_drive_backup(self):
self.do_test_stop("drive-backup", device="drive0",
--
2.29.2
next prev parent reply other threads:[~2021-01-18 11:03 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-18 10:57 [PATCH v5 00/10] iotests: Fix 129 and expand 297’s reach Max Reitz
2021-01-18 10:57 ` [PATCH v5 01/10] iotests.py: Assume a couple of variables as given Max Reitz
2021-01-26 21:00 ` John Snow
2021-01-18 10:57 ` [PATCH v5 02/10] iotests/297: Rewrite in Python and extend reach Max Reitz
2021-01-18 12:25 ` Vladimir Sementsov-Ogievskiy
2021-01-26 21:28 ` John Snow
2021-01-27 10:42 ` Max Reitz
2021-01-27 19:25 ` John Snow
2021-01-18 10:57 ` [PATCH v5 03/10] iotests: Move try_remove to iotests.py Max Reitz
2021-01-26 21:30 ` John Snow
2021-01-18 10:57 ` [PATCH v5 04/10] iotests/129: Remove test images in tearDown() Max Reitz
2021-01-18 10:57 ` [PATCH v5 05/10] iotests/129: Do not check @busy Max Reitz
2021-01-18 10:57 ` [PATCH v5 06/10] iotests/129: Use throttle node Max Reitz
2021-01-18 10:57 ` [PATCH v5 07/10] iotests/129: Actually test a commit job Max Reitz
2021-01-18 10:57 ` Max Reitz [this message]
2021-01-18 10:57 ` [PATCH v5 09/10] iotests/129: Clean up pylint and mypy complaints Max Reitz
2021-01-18 10:57 ` [PATCH v5 10/10] iotests/300: " Max Reitz
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210118105720.14824-9-mreitz@redhat.com \
--to=mreitz@redhat.com \
--cc=kwolf@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=vsementsov@virtuozzo.com \
--cc=wrampazz@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).