From: "Jürgen Groß" <jgross@suse.com>
To: Paul Durrant <pdurrant@amazon.com>,
xen-devel@lists.xenproject.org, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>,
"Roger Pau Monné" <roger.pau@citrix.com>,
"Jens Axboe" <axboe@kernel.dk>,
"Boris Ostrovsky" <boris.ostrovsky@oracle.com>,
"Stefano Stabellini" <sstabellini@kernel.org>
Subject: Re: [PATCH v3 4/4] xen-blkback: support dynamic unbind/bind
Date: Thu, 12 Dec 2019 07:07:06 +0100 [thread overview]
Message-ID: <d3c61bd0-c29f-bb73-f637-158c7541a5f3@suse.com> (raw)
In-Reply-To: <20191211152956.5168-5-pdurrant@amazon.com>
On 11.12.19 16:29, Paul Durrant wrote:
> By simply re-attaching to shared rings during connect_ring() rather than
> assuming they are freshly allocated (i.e assuming the counters are zero)
> it is possible for vbd instances to be unbound and re-bound from and to
> (respectively) a running guest.
>
> This has been tested by running:
>
> while true;
> do fio --name=randwrite --ioengine=libaio --iodepth=16 \
> --rw=randwrite --bs=4k --direct=1 --size=1G --verify=crc32;
> done
>
> in a PV guest whilst running:
>
> while true;
> do echo vbd-$DOMID-$VBD >unbind;
> echo unbound;
> sleep 5;
> echo vbd-$DOMID-$VBD >bind;
> echo bound;
> sleep 3;
> done
>
> in dom0 from /sys/bus/xen-backend/drivers/vbd to continuously unbind and
> re-bind its system disk image.
>
> This is a highly useful feature for a backend module as it allows it to be
> unloaded and re-loaded (i.e. updated) without requiring domUs to be halted.
> This was also tested by running:
>
> while true;
> do echo vbd-$DOMID-$VBD >unbind;
> echo unbound;
> sleep 5;
> rmmod xen-blkback;
> echo unloaded;
> sleep 1;
> modprobe xen-blkback;
> echo bound;
> cd $(pwd);
> sleep 3;
> done
>
> in dom0 whilst running the same loop as above in the (single) PV guest.
>
> Some (less stressful) testing has also been done using a Windows HVM guest
> with the latest 9.0 PV drivers installed.
>
> Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Juergen
WARNING: multiple messages have this Message-ID (diff)
From: "Jürgen Groß" <jgross@suse.com>
To: Paul Durrant <pdurrant@amazon.com>,
xen-devel@lists.xenproject.org, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: "Jens Axboe" <axboe@kernel.dk>,
"Boris Ostrovsky" <boris.ostrovsky@oracle.com>,
"Roger Pau Monné" <roger.pau@citrix.com>,
"Stefano Stabellini" <sstabellini@kernel.org>,
"Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>
Subject: Re: [Xen-devel] [PATCH v3 4/4] xen-blkback: support dynamic unbind/bind
Date: Thu, 12 Dec 2019 07:07:06 +0100 [thread overview]
Message-ID: <d3c61bd0-c29f-bb73-f637-158c7541a5f3@suse.com> (raw)
In-Reply-To: <20191211152956.5168-5-pdurrant@amazon.com>
On 11.12.19 16:29, Paul Durrant wrote:
> By simply re-attaching to shared rings during connect_ring() rather than
> assuming they are freshly allocated (i.e assuming the counters are zero)
> it is possible for vbd instances to be unbound and re-bound from and to
> (respectively) a running guest.
>
> This has been tested by running:
>
> while true;
> do fio --name=randwrite --ioengine=libaio --iodepth=16 \
> --rw=randwrite --bs=4k --direct=1 --size=1G --verify=crc32;
> done
>
> in a PV guest whilst running:
>
> while true;
> do echo vbd-$DOMID-$VBD >unbind;
> echo unbound;
> sleep 5;
> echo vbd-$DOMID-$VBD >bind;
> echo bound;
> sleep 3;
> done
>
> in dom0 from /sys/bus/xen-backend/drivers/vbd to continuously unbind and
> re-bind its system disk image.
>
> This is a highly useful feature for a backend module as it allows it to be
> unloaded and re-loaded (i.e. updated) without requiring domUs to be halted.
> This was also tested by running:
>
> while true;
> do echo vbd-$DOMID-$VBD >unbind;
> echo unbound;
> sleep 5;
> rmmod xen-blkback;
> echo unloaded;
> sleep 1;
> modprobe xen-blkback;
> echo bound;
> cd $(pwd);
> sleep 3;
> done
>
> in dom0 whilst running the same loop as above in the (single) PV guest.
>
> Some (less stressful) testing has also been done using a Windows HVM guest
> with the latest 9.0 PV drivers installed.
>
> Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Juergen
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
next prev parent reply other threads:[~2019-12-12 6:07 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-11 15:29 [PATCH v3 0/4] xen-blkback: support live update Paul Durrant
2019-12-11 15:29 ` [Xen-devel] " Paul Durrant
2019-12-11 15:29 ` [PATCH v3 1/4] xenbus: move xenbus_dev_shutdown() into frontend code Paul Durrant
2019-12-11 15:29 ` [Xen-devel] " Paul Durrant
2019-12-11 15:29 ` [PATCH v3 2/4] xenbus: limit when state is forced to closed Paul Durrant
2019-12-11 15:29 ` [Xen-devel] " Paul Durrant
2019-12-12 6:02 ` Jürgen Groß
2019-12-12 6:02 ` [Xen-devel] " Jürgen Groß
2019-12-11 15:29 ` [PATCH v3 3/4] xen/interface: re-define FRONT/BACK_RING_ATTACH() Paul Durrant
2019-12-11 15:29 ` [Xen-devel] " Paul Durrant
2019-12-12 6:04 ` Jürgen Groß
2019-12-12 6:04 ` [Xen-devel] " Jürgen Groß
2019-12-13 8:59 ` Jürgen Groß
2019-12-13 8:59 ` [Xen-devel] " Jürgen Groß
2019-12-13 9:02 ` Durrant, Paul
2019-12-13 9:02 ` [Xen-devel] " Durrant, Paul
2019-12-11 15:29 ` [PATCH v3 4/4] xen-blkback: support dynamic unbind/bind Paul Durrant
2019-12-11 15:29 ` [Xen-devel] " Paul Durrant
2019-12-12 6:07 ` Jürgen Groß [this message]
2019-12-12 6:07 ` Jürgen Groß
2019-12-12 11:46 ` Roger Pau Monné
2019-12-12 11:46 ` [Xen-devel] " Roger Pau Monné
2019-12-12 12:04 ` Jürgen Groß
2019-12-12 12:04 ` [Xen-devel] " Jürgen Groß
2019-12-20 12:45 ` [PATCH v3 0/4] xen-blkback: support live update Jürgen Groß
2019-12-20 12:45 ` [Xen-devel] " Jürgen Groß
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=d3c61bd0-c29f-bb73-f637-158c7541a5f3@suse.com \
--to=jgross@suse.com \
--cc=axboe@kernel.dk \
--cc=boris.ostrovsky@oracle.com \
--cc=konrad.wilk@oracle.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pdurrant@amazon.com \
--cc=roger.pau@citrix.com \
--cc=sstabellini@kernel.org \
--cc=xen-devel@lists.xenproject.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.