From: Eric Blake <1884831@bugs.launchpad.net>
To: qemu-devel@nongnu.org
Subject: [Bug 1884831] Re: qemu-nbd fails to discard bigger chunks
Date: Fri, 07 May 2021 12:30:28 -0000 [thread overview]
Message-ID: <162039062901.6177.17779935471683066697.malone@wampee.canonical.com> (raw)
In-Reply-To: 159294358125.13789.3860026407311199131.malonedeb@wampee.canonical.com
Commit 890cbccb0 included in upstream release 5.1.0.
** Changed in: qemu
Status: Incomplete => Fix Released
--
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1884831
Title:
qemu-nbd fails to discard bigger chunks
Status in QEMU:
Fix Released
Bug description:
This report is moved from systemd to here:
https://github.com/systemd/systemd/issues/16242
A qemu-nbd device reports that it can discard a lot of bytes:
cat /sys/block/nbd0/queue/discard_max_bytes
2199023255040
And indeed, discard works with small images:
$ qemu-img create -f qcow2 /tmp/image.img 2M
$ sudo qemu-nbd --connect=/dev/nbd0 /tmp/image.img
$ sudo blkdiscard /dev/nbd0
but not for bigger ones (still smaller than discard_max_bytes):
$ qemu-img create -f qcow2 /tmp/image.img 5G
$ sudo qemu-nbd --connect=/dev/nbd0 /tmp/image.img
$ sudo blkdiscard /dev/nbd0
To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1884831/+subscriptions
prev parent reply other threads:[~2021-05-07 12:50 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-23 20:19 [Bug 1884831] [NEW] qemu-nbd fails to discard bigger chunks TobiasHunger
2020-06-23 20:38 ` Eric Blake
2020-06-23 20:38 ` [Bug 1884831] " Eric Blake
2020-06-23 20:53 ` Eric Blake
2020-06-23 21:16 ` Eric Blake
2020-06-23 21:16 ` [Bug 1884831] [NEW] " Launchpad Bug Tracker
2020-06-23 21:35 ` [Bug 1884831] " Eric Blake
2020-07-22 21:41 ` Eric Blake
2020-07-22 21:41 ` Eric Blake
2021-05-07 2:53 ` Thomas Huth
2021-05-07 12:30 ` Eric Blake [this message]
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=162039062901.6177.17779935471683066697.malone@wampee.canonical.com \
--to=1884831@bugs.launchpad.net \
--cc=qemu-devel@nongnu.org \
/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).