All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Roger Pau Monné" <roger.pau@citrix.com>
To: David Vrabel <david.vrabel@citrix.com>
Cc: <xen-devel@lists.xen.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [Xen-devel] [PATCH RFC 3/4] xen-blkfront: prevent hoarding all grants
Date: Thu, 11 Jul 2013 16:57:12 +0200	[thread overview]
Message-ID: <51DEC7C8.1090509@citrix.com> (raw)
In-Reply-To: <51DEB3D5.2050101@citrix.com>

On 11/07/13 15:32, David Vrabel wrote:
> On 08/07/13 14:03, Roger Pau Monne wrote:
>> Prevent blkfront from hoarding all grants by adding a minimum number
>> of grants that must be free at all times. We still need a way to free
>> unused grants in blkfront, but this patch will mitigate the problem
>> in the meantime.
> 
> I think this could end up with the a frontend being able to get no
> grants because some other frontend always grabs the free grants first.
> 
> Particularly as the free grant callbacks are done in the wrong order.

I'm not so sure this patch is worth pushing any more, given that we will
be freeing grants instead of keeping them all in blkfront.

It seems like it might still be useful if we are under a lot of IO
pressure on different blkfronts and for example wanted to hot-attach a
new network interface (which requires 512 grants).

  parent reply	other threads:[~2013-07-11 14:57 UTC|newest]

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-08 13:03 [PATCH RFC 0/4] xen-block: prevent blkfront for hoarding grants Roger Pau Monne
2013-07-08 13:03 ` [PATCH RFC 1/4] xen-gnt: prevent adding duplicate gnt callbacks Roger Pau Monne
2013-07-08 13:03   ` Roger Pau Monne
2013-07-11 13:17   ` David Vrabel
2013-07-11 13:17   ` [Xen-devel] " David Vrabel
2013-07-11 16:23     ` Roger Pau Monné
2013-07-11 16:23     ` Roger Pau Monné
2013-07-08 13:03 ` [PATCH RFC 2/4] xen-blkfront: improve aproximation of required grants per request Roger Pau Monne
2013-07-08 13:03 ` Roger Pau Monne
2013-07-11 13:20   ` [Xen-devel] " David Vrabel
2013-07-11 14:47     ` Roger Pau Monné
2013-07-11 14:47     ` Roger Pau Monné
2013-07-11 13:20   ` David Vrabel
2013-07-08 13:03 ` [PATCH RFC 3/4] xen-blkfront: prevent hoarding all grants Roger Pau Monne
2013-07-11 13:32   ` David Vrabel
2013-07-11 13:32   ` [Xen-devel] " David Vrabel
2013-07-11 14:57     ` Roger Pau Monné
2013-07-11 14:57     ` Roger Pau Monné [this message]
2013-07-08 13:03 ` Roger Pau Monne
2013-07-08 13:03 ` [PATCH RFC 4/4] xen-block: introduce a new request type to unmap grants Roger Pau Monne
2013-07-08 19:41   ` Konrad Rzeszutek Wilk
2013-07-09 13:22     ` Wei Liu
2013-07-09 13:22     ` [Xen-devel] " Wei Liu
2013-07-09 16:37     ` Roger Pau Monné
2013-07-09 16:37     ` Roger Pau Monné
2013-07-09 18:32       ` Konrad Rzeszutek Wilk
2013-07-09 18:38         ` [Xen-devel] " Wei Liu
2013-07-09 18:38         ` Wei Liu
2013-07-09 18:32       ` Konrad Rzeszutek Wilk
2013-07-10  9:19     ` Roger Pau Monné
2013-07-10  9:19     ` Roger Pau Monné
2013-07-10 13:54       ` Egger, Christoph
2013-07-10 13:54       ` [Xen-devel] " Egger, Christoph
2013-07-10 14:46         ` Roger Pau Monné
2013-07-10 14:46         ` Roger Pau Monné
2013-07-10 14:52       ` Konrad Rzeszutek Wilk
2013-07-10 14:52       ` Konrad Rzeszutek Wilk
2013-07-11 13:48       ` David Vrabel
2013-07-11 13:48       ` [Xen-devel] " David Vrabel
2013-07-11 15:12         ` Roger Pau Monné
2013-07-11 15:12           ` Roger Pau Monné
2013-07-11 15:26           ` David Vrabel
2013-07-11 15:26           ` [Xen-devel] " David Vrabel
2013-07-11 15:48             ` Roger Pau Monné
2013-07-12 10:12               ` David Vrabel
2013-07-12 10:12               ` David Vrabel
2013-07-11 15:48             ` Roger Pau Monné
2013-07-08 19:41   ` Konrad Rzeszutek Wilk
2013-07-08 13:03 ` Roger Pau Monne
2013-07-11 13:35 ` [Xen-devel] [PATCH RFC 0/4] xen-block: prevent blkfront for hoarding grants David Vrabel
2013-07-11 13:35 ` David Vrabel
2013-07-31  9:50 ` Roger Pau Monné
2013-07-31  9:50 ` [Xen-devel] " Roger Pau Monné
2013-07-31 11:27   ` Konrad Rzeszutek Wilk
2013-07-31 11:27   ` [Xen-devel] " Konrad Rzeszutek Wilk

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=51DEC7C8.1090509@citrix.com \
    --to=roger.pau@citrix.com \
    --cc=david.vrabel@citrix.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=xen-devel@lists.xen.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.