From: Leon Romanovsky <leon@kernel.org>
To: Max Gurtovoy <mgurtovoy@nvidia.com>
Cc: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>,
hch@infradead.org, mst@redhat.com,
virtualization@lists.linux-foundation.org, kvm@vger.kernel.org,
stefanha@redhat.com, israelr@nvidia.com, nitzanc@nvidia.com,
oren@nvidia.com, linux-block@vger.kernel.org, axboe@kernel.dk
Subject: Re: [PATCH v3 1/1] virtio-blk: add num_request_queues module parameter
Date: Sun, 5 Sep 2021 13:19:18 +0300 [thread overview]
Message-ID: <YTSZpm1GZGT4BUDR@unreal> (raw)
In-Reply-To: <e4455133-ac9f-44d0-a07d-be55b336ebcc@nvidia.com>
On Sun, Sep 05, 2021 at 12:19:09PM +0300, Max Gurtovoy wrote:
>
> On 9/5/2021 11:49 AM, Chaitanya Kulkarni wrote:
> >
> > On 9/5/2021 12:46 AM, Leon Romanovsky wrote:
> > > > +static unsigned int num_request_queues;
> > > > +module_param_cb(num_request_queues, &queue_count_ops,
> > > > &num_request_queues,
> > > > + 0644);
> > > > +MODULE_PARM_DESC(num_request_queues,
> > > > + "Number of request queues to use for blk device.
> > > > Should > 0");
> > > > +
> > > Won't it limit all virtio block devices to the same limit?
> > >
> > > It is very common to see multiple virtio-blk devices on the same system
> > > and they probably need different limits.
> > >
> > > Thanks
> >
> >
> > Without looking into the code, that can be done adding a configfs
> >
> > interface and overriding a global value (module param) when it is set
> > from
> >
> > configfs.
> >
> >
> You have many ways to overcome this issue.
>
> For example:
>
> # ls -l /sys/block/vda/mq/
> drwxr-xr-x 18 root root 0 Sep 5 12:14 0
> drwxr-xr-x 18 root root 0 Sep 5 12:14 1
> drwxr-xr-x 18 root root 0 Sep 5 12:14 2
> drwxr-xr-x 18 root root 0 Sep 5 12:14 3
>
> # echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/unbind
>
> # echo 8 > /sys/module/virtio_blk/parameters/num_request_queues
This is global to all virtio-blk devices.
>
> # echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/bind
>
> # ls -l /sys/block/vda/mq/
> drwxr-xr-x 10 root root 0 Sep 5 12:17 0
> drwxr-xr-x 10 root root 0 Sep 5 12:17 1
> drwxr-xr-x 10 root root 0 Sep 5 12:17 2
> drwxr-xr-x 10 root root 0 Sep 5 12:17 3
> drwxr-xr-x 10 root root 0 Sep 5 12:17 4
> drwxr-xr-x 10 root root 0 Sep 5 12:17 5
> drwxr-xr-x 10 root root 0 Sep 5 12:17 6
> drwxr-xr-x 10 root root 0 Sep 5 12:17 7
>
> -Max.
>
>
WARNING: multiple messages have this Message-ID (diff)
From: Leon Romanovsky <leon@kernel.org>
To: Max Gurtovoy <mgurtovoy@nvidia.com>
Cc: axboe@kernel.dk, linux-block@vger.kernel.org,
kvm@vger.kernel.org, mst@redhat.com, israelr@nvidia.com,
nitzanc@nvidia.com, virtualization@lists.linux-foundation.org,
hch@infradead.org, Chaitanya Kulkarni <ckulkarnilinux@gmail.com>,
stefanha@redhat.com, oren@nvidia.com
Subject: Re: [PATCH v3 1/1] virtio-blk: add num_request_queues module parameter
Date: Sun, 5 Sep 2021 13:19:18 +0300 [thread overview]
Message-ID: <YTSZpm1GZGT4BUDR@unreal> (raw)
In-Reply-To: <e4455133-ac9f-44d0-a07d-be55b336ebcc@nvidia.com>
On Sun, Sep 05, 2021 at 12:19:09PM +0300, Max Gurtovoy wrote:
>
> On 9/5/2021 11:49 AM, Chaitanya Kulkarni wrote:
> >
> > On 9/5/2021 12:46 AM, Leon Romanovsky wrote:
> > > > +static unsigned int num_request_queues;
> > > > +module_param_cb(num_request_queues, &queue_count_ops,
> > > > &num_request_queues,
> > > > + 0644);
> > > > +MODULE_PARM_DESC(num_request_queues,
> > > > + "Number of request queues to use for blk device.
> > > > Should > 0");
> > > > +
> > > Won't it limit all virtio block devices to the same limit?
> > >
> > > It is very common to see multiple virtio-blk devices on the same system
> > > and they probably need different limits.
> > >
> > > Thanks
> >
> >
> > Without looking into the code, that can be done adding a configfs
> >
> > interface and overriding a global value (module param) when it is set
> > from
> >
> > configfs.
> >
> >
> You have many ways to overcome this issue.
>
> For example:
>
> # ls -l /sys/block/vda/mq/
> drwxr-xr-x 18 root root 0 Sep 5 12:14 0
> drwxr-xr-x 18 root root 0 Sep 5 12:14 1
> drwxr-xr-x 18 root root 0 Sep 5 12:14 2
> drwxr-xr-x 18 root root 0 Sep 5 12:14 3
>
> # echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/unbind
>
> # echo 8 > /sys/module/virtio_blk/parameters/num_request_queues
This is global to all virtio-blk devices.
>
> # echo virtio0 > /sys/bus/virtio/drivers/virtio_blk/bind
>
> # ls -l /sys/block/vda/mq/
> drwxr-xr-x 10 root root 0 Sep 5 12:17 0
> drwxr-xr-x 10 root root 0 Sep 5 12:17 1
> drwxr-xr-x 10 root root 0 Sep 5 12:17 2
> drwxr-xr-x 10 root root 0 Sep 5 12:17 3
> drwxr-xr-x 10 root root 0 Sep 5 12:17 4
> drwxr-xr-x 10 root root 0 Sep 5 12:17 5
> drwxr-xr-x 10 root root 0 Sep 5 12:17 6
> drwxr-xr-x 10 root root 0 Sep 5 12:17 7
>
> -Max.
>
>
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
next prev parent reply other threads:[~2021-09-05 10:19 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-02 20:46 [PATCH v3 1/1] virtio-blk: add num_request_queues module parameter Max Gurtovoy
2021-09-03 6:06 ` Pankaj Gupta
2021-09-05 7:46 ` Leon Romanovsky
2021-09-05 7:46 ` Leon Romanovsky
2021-09-05 8:49 ` Chaitanya Kulkarni
2021-09-05 9:19 ` Max Gurtovoy
2021-09-05 10:19 ` Leon Romanovsky [this message]
2021-09-05 10:19 ` Leon Romanovsky
2021-09-05 11:16 ` Max Gurtovoy
2021-09-05 13:10 ` Leon Romanovsky
2021-09-05 13:10 ` Leon Romanovsky
2021-09-05 13:16 ` Max Gurtovoy
2021-09-05 10:20 ` Leon Romanovsky
2021-09-05 10:20 ` Leon Romanovsky
2021-09-05 15:15 ` Michael S. Tsirkin
2021-09-05 15:15 ` Michael S. Tsirkin
2021-09-07 23:04 ` Leon Romanovsky
2021-09-07 23:04 ` Leon Romanovsky
2021-10-22 9:30 ` Michael S. Tsirkin
2021-10-22 9:30 ` Michael S. Tsirkin
2021-10-24 7:19 ` Max Gurtovoy
2021-10-24 8:12 ` Max Gurtovoy
2021-10-24 8:48 ` Michael S. Tsirkin
2021-10-24 8:48 ` Michael S. Tsirkin
2021-10-24 10:57 ` Max Gurtovoy
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=YTSZpm1GZGT4BUDR@unreal \
--to=leon@kernel.org \
--cc=axboe@kernel.dk \
--cc=ckulkarnilinux@gmail.com \
--cc=hch@infradead.org \
--cc=israelr@nvidia.com \
--cc=kvm@vger.kernel.org \
--cc=linux-block@vger.kernel.org \
--cc=mgurtovoy@nvidia.com \
--cc=mst@redhat.com \
--cc=nitzanc@nvidia.com \
--cc=oren@nvidia.com \
--cc=stefanha@redhat.com \
--cc=virtualization@lists.linux-foundation.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.