RE: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sunday, March 12, 2017 12:04 PM, Michael S. Tsirkin wrote: > On Sun, Mar 12, 2017 at 01:59:54AM +, Wang, Wei W wrote: > > On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > > > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > > > I'm thinking what if the guest needs to transfer

RE: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sunday, March 12, 2017 12:04 PM, Michael S. Tsirkin wrote: > On Sun, Mar 12, 2017 at 01:59:54AM +, Wang, Wei W wrote: > > On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > > > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > > > I'm thinking what if the guest needs to transfer

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sun, Mar 12, 2017 at 01:59:54AM +, Wang, Wei W wrote: > On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > > I'm thinking what if the guest needs to transfer these much physically > > > continuous memory to host:

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sun, Mar 12, 2017 at 01:59:54AM +, Wang, Wei W wrote: > On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > > I'm thinking what if the guest needs to transfer these much physically > > > continuous memory to host:

RE: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > I'm thinking what if the guest needs to transfer these much physically > > continuous memory to host: 1GB+2MB+64KB+32KB+16KB+4KB. > > Is it going to use Six 64-bit chunks? Would it be

RE: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/11/2017 10:10 PM, Matthew Wilcox wrote: > On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > > I'm thinking what if the guest needs to transfer these much physically > > continuous memory to host: 1GB+2MB+64KB+32KB+16KB+4KB. > > Is it going to use Six 64-bit chunks? Would it be

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > On 03/11/2017 01:11 AM, Matthew Wilcox wrote: > > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > > One of the issues of current balloon is the 4k page size > > > assumption. For example if you free a huge page you

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > On 03/11/2017 01:11 AM, Matthew Wilcox wrote: > > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > > One of the issues of current balloon is the 4k page size > > > assumption. For example if you free a huge page you

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 01:25:41PM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 09:35:21PM +0200, Michael S. Tsirkin wrote: > > > bit 0 clear => bits 1-11 encode a page count, bits 12-63 encode a PFN, > > > page size 4k. > > > bit 0 set, bit 1 clear => bits 2-12 encode a page count,

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 01:25:41PM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 09:35:21PM +0200, Michael S. Tsirkin wrote: > > > bit 0 clear => bits 1-11 encode a page count, bits 12-63 encode a PFN, > > > page size 4k. > > > bit 0 set, bit 1 clear => bits 2-12 encode a page count,

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > I'm thinking what if the guest needs to transfer these much physically > continuous > memory to host: 1GB+2MB+64KB+32KB+16KB+4KB. > Is it going to use Six 64-bit chunks? Would it be simpler if we just > use the 128-bit chunk format (we

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Sat, Mar 11, 2017 at 07:59:31PM +0800, Wei Wang wrote: > I'm thinking what if the guest needs to transfer these much physically > continuous > memory to host: 1GB+2MB+64KB+32KB+16KB+4KB. > Is it going to use Six 64-bit chunks? Would it be simpler if we just > use the 128-bit chunk format (we

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/11/2017 01:11 AM, Matthew Wilcox wrote: On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: One of the issues of current balloon is the 4k page size assumption. For example if you free a huge page you have to split it up and pass 4k chunks to host. Quite often host can't

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/11/2017 01:11 AM, Matthew Wilcox wrote: On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: One of the issues of current balloon is the 4k page size assumption. For example if you free a huge page you have to split it up and pass 4k chunks to host. Quite often host can't

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:35:21PM +0200, Michael S. Tsirkin wrote: > > bit 0 clear => bits 1-11 encode a page count, bits 12-63 encode a PFN, page > > size 4k. > > bit 0 set, bit 1 clear => bits 2-12 encode a page count, bits 13-63 encode > > a PFN, page size 8k > > bits 0+1 set, bit 2 clear =>

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:35:21PM +0200, Michael S. Tsirkin wrote: > > bit 0 clear => bits 1-11 encode a page count, bits 12-63 encode a PFN, page > > size 4k. > > bit 0 set, bit 1 clear => bits 2-12 encode a page count, bits 13-63 encode > > a PFN, page size 8k > > bits 0+1 set, bit 2 clear =>

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:10:53PM +0200, Michael S. Tsirkin wrote: > > I completely agree with you that we should be able to pass a hugepage > > as a single chunk. Also we shouldn't assume that host and guest have > > the same page size. I think we can come up with a scheme that actually > >

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:10:53PM +0200, Michael S. Tsirkin wrote: > > I completely agree with you that we should be able to pass a hugepage > > as a single chunk. Also we shouldn't assume that host and guest have > > the same page size. I think we can come up with a scheme that actually > >

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:11:44AM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > One of the issues of current balloon is the 4k page size > > assumption. For example if you free a huge page you > > have to split it up and pass 4k chunks to

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:11:44AM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > One of the issues of current balloon is the 4k page size > > assumption. For example if you free a huge page you > > have to split it up and pass 4k chunks to

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:11:44AM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > One of the issues of current balloon is the 4k page size > > assumption. For example if you free a huge page you > > have to split it up and pass 4k chunks to

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 09:11:44AM -0800, Matthew Wilcox wrote: > On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > > One of the issues of current balloon is the 4k page size > > assumption. For example if you free a huge page you > > have to split it up and pass 4k chunks to

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > One of the issues of current balloon is the 4k page size > assumption. For example if you free a huge page you > have to split it up and pass 4k chunks to host. > Quite often host can't free these 4k chunks at all (e.g. > when

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 05:58:28PM +0200, Michael S. Tsirkin wrote: > One of the issues of current balloon is the 4k page size > assumption. For example if you free a huge page you > have to split it up and pass 4k chunks to host. > Quite often host can't free these 4k chunks at all (e.g. > when

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 07:37:28PM +0800, Wei Wang wrote: > On 03/09/2017 10:14 PM, Matthew Wilcox wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li > > > 1) allocating pages (6.5%) > > > 2) sending PFNs to host (68.3%) > > > 3)

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 07:37:28PM +0800, Wei Wang wrote: > On 03/09/2017 10:14 PM, Matthew Wilcox wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li > > > 1) allocating pages (6.5%) > > > 2) sending PFNs to host (68.3%) > > > 3) address translation (6.1%) >

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 06:02:31PM +0800, Wei Wang wrote: > On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li > > > > > > The implementation of the current virtio-balloon is not very > > >

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 10, 2017 at 06:02:31PM +0800, Wei Wang wrote: > On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li > > > > > > The implementation of the current virtio-balloon is not very > > > efficient, because the

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

Am 10.03.2017 um 11:02 schrieb Wei Wang: > On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: >> On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: >>> From: Liang Li >>> >>> The implementation of the current virtio-balloon is not very >>> efficient, because the pages

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

Am 10.03.2017 um 11:02 schrieb Wei Wang: > On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: >> On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: >>> From: Liang Li >>> >>> The implementation of the current virtio-balloon is not very >>> efficient, because the pages are transferred to the

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/09/2017 10:14 PM, Matthew Wilcox wrote: On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: From: Liang Li 1) allocating pages (6.5%) 2) sending PFNs to host (68.3%) 3) address translation (6.1%) 4) madvise (19%) This patch optimizes step 2) by transfering

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/09/2017 10:14 PM, Matthew Wilcox wrote: On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: From: Liang Li 1) allocating pages (6.5%) 2) sending PFNs to host (68.3%) 3) address translation (6.1%) 4) madvise (19%) This patch optimizes step 2) by transfering pages to the host in

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: From: Liang Li The implementation of the current virtio-balloon is not very efficient, because the pages are transferred to the host one by one. Here is the

Re: [virtio-dev] Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On 03/08/2017 12:01 PM, Michael S. Tsirkin wrote: On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: From: Liang Li The implementation of the current virtio-balloon is not very efficient, because the pages are transferred to the host one by one. Here is the breakdown of the time in

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li > 1) allocating pages (6.5%) > 2) sending PFNs to host (68.3%) > 3) address translation (6.1%) > 4) madvise (19%) > > This patch optimizes step 2) by transfering pages to the host in > chunks. A

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li > 1) allocating pages (6.5%) > 2) sending PFNs to host (68.3%) > 3) address translation (6.1%) > 4) madvise (19%) > > This patch optimizes step 2) by transfering pages to the host in > chunks. A chunk consists of guest

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li > > The implementation of the current virtio-balloon is not very > efficient, because the pages are transferred to the host one by one. > Here is the breakdown of the time in percentage spent on each

Re: [PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li > > The implementation of the current virtio-balloon is not very > efficient, because the pages are transferred to the host one by one. > Here is the breakdown of the time in percentage spent on each > step of the balloon

[PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

From: Liang Li The implementation of the current virtio-balloon is not very efficient, because the pages are transferred to the host one by one. Here is the breakdown of the time in percentage spent on each step of the balloon inflating process (inflating 7GB of an 8GB idle

[PATCH v7 kernel 3/5] virtio-balloon: implementation of VIRTIO_BALLOON_F_CHUNK_TRANSFER

From: Liang Li The implementation of the current virtio-balloon is not very efficient, because the pages are transferred to the host one by one. Here is the breakdown of the time in percentage spent on each step of the balloon inflating process (inflating 7GB of an 8GB idle guest). 1)