From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?VG9tw6HFoSBHb2xlbWJpb3Zza8O9?= Subject: Re: [Qemu-devel] [RFC] Buffers/caches in VirtIO Balloon driver stats Date: Tue, 12 Sep 2017 21:23:35 +0200 Message-ID: <20170912212335.34f42ec7@fiorina> References: <20170827233033.7afa49b9@fiorina> <20170829095726.GL25960@stefanha-x1.localdomain> <59A557B1.7080704@intel.com> <20170912162947.130c2df2@fiorina> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: Stefan Hajnoczi , qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, "Michael S. Tsirkin" To: Wei Wang Return-path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: In-Reply-To: <20170912162947.130c2df2@fiorina> List-Id: kvm.vger.kernel.org Resending. It did not reach virtio-dev the first time. On Tue, 12 Sep 2017 16:29:47 +0200 Tom=C3=A1=C5=A1 Golembiovsk=C3=BD wrote: > On Tue, 29 Aug 2017 20:01:53 +0800 > Wei Wang wrote: >=20 > > On 08/29/2017 05:57 PM, Stefan Hajnoczi wrote: > > > On Sun, Aug 27, 2017 at 11:30:33PM +0200, Tom=C3=A1=C5=A1 Golembiovsk= =C3=BD wrote: =20 > > >> Hi, =20 > > > I have CCed the relevant mailing lists and people most recently invol= ved > > > in virtio-balloon discussions. Hopefully this will help get the right > > > people to see your questions. > > > =20 > > >> We'd like to include information about reclaimable memory into the > > >> statistics in VirtiO Balloon driver. Namely, we'd like to include > > >> counters for bufferes and caches of Linux kernel. The patch itself is > > >> pretty trivial -- no problem there. But before we do that I'd like to > > >> get some input from the QEMU community. > > >> > > >> 1) Is there any reason not to have the stats there? =20 > >=20 > > Could you please share the usages of reclaimable memory via the stats? >=20 > I'll go ahead then and start sending patches. What would be the proper > course of action here? Send patch for the driver first, or send patch > for QEMU first or send both patches right away? >=20 >=20 > > >> > > >> 2) Considering the balloon device is multiplatform (Linux, BSD, > > >> Windows), is there a problem with including buffers/caches? These se= em > > >> to be specific to the Linux virtual memory subsystem. Of course, oth= er > > >> OSes could just report zeros. Are there some internal stats on those > > >> OSes that could be filled in? I don't now if such or similar statist= ic > > >> are available on BSD. On Windows only SystemCache stat looks like > > >> something relevant. Anyone familiar with those OSes has any suggesti= ons? > > >> > > >> =20 > >=20 > > One of the solutions that I'm thinking about is to make virtio=20 > > platform-ware. >=20 > This is not necessary. IIUC the driver does not need to send all the > stats. We can simply treat those stats as specific to Linux driver and > other drivers will not send them. Then QEMU will treat them as if zero > was reported. >=20 > >=20 > > That is, the device by default supports > > VIRTIO_F_LINUX, > > VIRTIO_F_WINDOWS, > > VIRTIO_F_BSD. > >=20 > > For the Linux driver, only VIRTIO_F_LINUX is supported, then we can > > have Linux specific driver implementations under that feature. >=20 >=20 > Since there were no suggestions for similar stats on other OSes I'd say > we treat the stats for buffers and caches as Linux specific. If there is > any need to send similar stats for other OSes we will add new stat fields > (specific for that particular OS). >=20 >=20 > Thanks, >=20 > Tomas >=20 > --=20 > Tom=C3=A1=C5=A1 Golembiovsk=C3=BD --=20 Tom=C3=A1=C5=A1 Golembiovsk=C3=BD From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-2537-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [66.179.20.138]) by lists.oasis-open.org (Postfix) with ESMTP id 61A3D58191DF for ; Tue, 12 Sep 2017 12:23:40 -0700 (PDT) Date: Tue, 12 Sep 2017 21:23:35 +0200 From: =?UTF-8?B?VG9tw6HFoSBHb2xlbWJpb3Zza8O9?= Message-ID: <20170912212335.34f42ec7@fiorina> In-Reply-To: <20170912162947.130c2df2@fiorina> References: <20170827233033.7afa49b9@fiorina> <20170829095726.GL25960@stefanha-x1.localdomain> <59A557B1.7080704@intel.com> <20170912162947.130c2df2@fiorina> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [virtio-dev] Re: [Qemu-devel] [RFC] Buffers/caches in VirtIO Balloon driver stats To: Wei Wang Cc: Stefan Hajnoczi , qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, "Michael S. Tsirkin" List-ID: Resending. It did not reach virtio-dev the first time. On Tue, 12 Sep 2017 16:29:47 +0200 Tom=C3=A1=C5=A1 Golembiovsk=C3=BD wrote: > On Tue, 29 Aug 2017 20:01:53 +0800 > Wei Wang wrote: >=20 > > On 08/29/2017 05:57 PM, Stefan Hajnoczi wrote: > > > On Sun, Aug 27, 2017 at 11:30:33PM +0200, Tom=C3=A1=C5=A1 Golembiovsk= =C3=BD wrote: =20 > > >> Hi, =20 > > > I have CCed the relevant mailing lists and people most recently invol= ved > > > in virtio-balloon discussions. Hopefully this will help get the right > > > people to see your questions. > > > =20 > > >> We'd like to include information about reclaimable memory into the > > >> statistics in VirtiO Balloon driver. Namely, we'd like to include > > >> counters for bufferes and caches of Linux kernel. The patch itself is > > >> pretty trivial -- no problem there. But before we do that I'd like to > > >> get some input from the QEMU community. > > >> > > >> 1) Is there any reason not to have the stats there? =20 > >=20 > > Could you please share the usages of reclaimable memory via the stats? >=20 > I'll go ahead then and start sending patches. What would be the proper > course of action here? Send patch for the driver first, or send patch > for QEMU first or send both patches right away? >=20 >=20 > > >> > > >> 2) Considering the balloon device is multiplatform (Linux, BSD, > > >> Windows), is there a problem with including buffers/caches? These se= em > > >> to be specific to the Linux virtual memory subsystem. Of course, oth= er > > >> OSes could just report zeros. Are there some internal stats on those > > >> OSes that could be filled in? I don't now if such or similar statist= ic > > >> are available on BSD. On Windows only SystemCache stat looks like > > >> something relevant. Anyone familiar with those OSes has any suggesti= ons? > > >> > > >> =20 > >=20 > > One of the solutions that I'm thinking about is to make virtio=20 > > platform-ware. >=20 > This is not necessary. IIUC the driver does not need to send all the > stats. We can simply treat those stats as specific to Linux driver and > other drivers will not send them. Then QEMU will treat them as if zero > was reported. >=20 > >=20 > > That is, the device by default supports > > VIRTIO_F_LINUX, > > VIRTIO_F_WINDOWS, > > VIRTIO_F_BSD. > >=20 > > For the Linux driver, only VIRTIO_F_LINUX is supported, then we can > > have Linux specific driver implementations under that feature. >=20 >=20 > Since there were no suggestions for similar stats on other OSes I'd say > we treat the stats for buffers and caches as Linux specific. If there is > any need to send similar stats for other OSes we will add new stat fields > (specific for that particular OS). >=20 >=20 > Thanks, >=20 > Tomas >=20 > --=20 > Tom=C3=A1=C5=A1 Golembiovsk=C3=BD --=20 Tom=C3=A1=C5=A1 Golembiovsk=C3=BD --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org