From: Rik van Riel <riel@redhat.com>
To: Frank Swiderski <fes@google.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>,
"Michael S. Tsirkin" <mst@redhat.com>,
Andrea Arcangeli <aarcange@redhat.com>,
virtualization@lists.linux-foundation.org,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
mikew@google.com, Ying Han <yinghan@google.com>,
Rafael Aquini <aquini@redhat.com>
Subject: Re: [PATCH] Add a page cache-backed balloon device driver.
Date: Tue, 26 Jun 2012 16:40:14 -0400 [thread overview]
Message-ID: <4FEA1E2E.4020806@redhat.com> (raw)
In-Reply-To: <1340742778-11282-1-git-send-email-fes@google.com>
On 06/26/2012 04:32 PM, Frank Swiderski wrote:
> This implementation of a virtio balloon driver uses the page cache to
> "store" pages that have been released to the host. The communication
> (outside of target counts) is one way--the guest notifies the host when
> it adds a page to the page cache, allowing the host to madvise(2) with
> MADV_DONTNEED. Reclaim in the guest is therefore automatic and implicit
> (via the regular page reclaim). This means that inflating the balloon
> is similar to the existing balloon mechanism, but the deflate is
> different--it re-uses existing Linux kernel functionality to
> automatically reclaim.
>
> Signed-off-by: Frank Swiderski<fes@google.com>
It is a great idea, but how can this memory balancing
possibly work if someone uses memory cgroups inside a
guest?
Having said that, we currently do not have proper
memory reclaim balancing between cgroups at all, so
requiring that of this balloon driver would be
unreasonable.
The code looks good to me, my only worry is the
code duplication. We now have 5 balloon drivers,
for 4 hypervisors, all implementing everything
from scratch...
WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Frank Swiderski <fes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>,
Rafael Aquini <aquini@redhat.com>,
kvm@vger.kernel.org, "Michael S. Tsirkin" <mst@redhat.com>,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org,
Ying Han <yinghan@google.com>,
mikew@google.com
Subject: Re: [PATCH] Add a page cache-backed balloon device driver.
Date: Tue, 26 Jun 2012 16:40:14 -0400 [thread overview]
Message-ID: <4FEA1E2E.4020806@redhat.com> (raw)
In-Reply-To: <1340742778-11282-1-git-send-email-fes@google.com>
On 06/26/2012 04:32 PM, Frank Swiderski wrote:
> This implementation of a virtio balloon driver uses the page cache to
> "store" pages that have been released to the host. The communication
> (outside of target counts) is one way--the guest notifies the host when
> it adds a page to the page cache, allowing the host to madvise(2) with
> MADV_DONTNEED. Reclaim in the guest is therefore automatic and implicit
> (via the regular page reclaim). This means that inflating the balloon
> is similar to the existing balloon mechanism, but the deflate is
> different--it re-uses existing Linux kernel functionality to
> automatically reclaim.
>
> Signed-off-by: Frank Swiderski<fes@google.com>
It is a great idea, but how can this memory balancing
possibly work if someone uses memory cgroups inside a
guest?
Having said that, we currently do not have proper
memory reclaim balancing between cgroups at all, so
requiring that of this balloon driver would be
unreasonable.
The code looks good to me, my only worry is the
code duplication. We now have 5 balloon drivers,
for 4 hypervisors, all implementing everything
from scratch...
next prev parent reply other threads:[~2012-06-26 20:41 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-26 20:32 [PATCH] Add a page cache-backed balloon device driver Frank Swiderski
2012-06-26 20:40 ` Rik van Riel [this message]
2012-06-26 20:40 ` Rik van Riel
2012-06-26 21:31 ` Frank Swiderski
2012-06-26 21:31 ` Frank Swiderski
2012-06-26 21:45 ` Rik van Riel
2012-06-26 21:45 ` Rik van Riel
2012-06-26 23:45 ` Frank Swiderski
2012-06-27 9:04 ` Michael S. Tsirkin
2012-06-27 9:04 ` Michael S. Tsirkin
2012-06-26 21:47 ` Michael S. Tsirkin
2012-06-26 21:47 ` Michael S. Tsirkin
2012-06-26 23:21 ` Frank Swiderski
2012-06-26 23:21 ` Frank Swiderski
2012-06-27 9:02 ` Michael S. Tsirkin
2012-06-27 9:02 ` Michael S. Tsirkin
2012-07-02 0:29 ` Rusty Russell
2012-07-02 0:29 ` Rusty Russell
2012-09-03 6:35 ` Paolo Bonzini
2012-09-03 6:35 ` Paolo Bonzini
2012-09-06 1:35 ` Rusty Russell
2012-09-06 1:35 ` Rusty Russell
2012-06-26 21:41 ` Michael S. Tsirkin
2012-06-26 21:41 ` Michael S. Tsirkin
2012-06-27 2:56 ` Rusty Russell
2012-06-27 2:56 ` Rusty Russell
2012-06-27 15:48 ` Frank Swiderski
2012-06-27 15:48 ` Frank Swiderski
2012-06-27 16:06 ` Michael S. Tsirkin
2012-06-27 16:06 ` Michael S. Tsirkin
2012-06-27 16:08 ` Frank Swiderski
2012-06-27 16:08 ` Frank Swiderski
2012-06-27 9:40 ` Amit Shah
2012-06-27 9:40 ` Amit Shah
2012-08-30 8:57 ` Michael S. Tsirkin
2012-08-30 8:57 ` Michael S. Tsirkin
2012-09-03 15:09 ` Avi Kivity
2012-09-03 15:09 ` Avi Kivity
2012-09-10 9:05 ` Michael S. Tsirkin
2012-09-10 9:05 ` Michael S. Tsirkin
2012-09-10 17:37 ` Mike Waychison
2012-09-10 17:37 ` Mike Waychison
2012-09-10 18:04 ` Rik van Riel
2012-09-10 18:04 ` Rik van Riel
2012-09-10 18:29 ` Mike Waychison
2012-09-10 18:29 ` Mike Waychison
2012-09-10 19:59 ` Michael S. Tsirkin
2012-09-10 19:59 ` Michael S. Tsirkin
2012-09-10 19:59 ` Michael S. Tsirkin
2012-09-10 20:49 ` Mike Waychison
2012-09-10 20:49 ` Mike Waychison
2012-09-10 21:10 ` Michael S. Tsirkin
2012-09-10 21:10 ` Michael S. Tsirkin
2012-10-30 15:29 ` Michael S. Tsirkin
2012-10-30 15:29 ` Michael S. Tsirkin
2012-10-30 16:25 ` Mike Waychison
2012-10-30 16:25 ` Mike Waychison
2012-09-12 5:25 ` Rusty Russell
2012-09-12 5:25 ` Rusty Russell
2012-06-26 20:32 Frank Swiderski
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