search for: chunk_ext

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li <liang.z.li at intel.com> > 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 physically continuous pages, and > it is

On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > From: Liang Li <liang.z.li at intel.com> > 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 physically continuous pages, and > it is

...54,16 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); >> static struct vfsmount *balloon_mnt; >> #endif >> >> +struct balloon_page_chunk { >> + __le64 base : 52; >> + __le64 size : 12; >> +}; >> + >> +struct balloon_page_chunk_ext { >> + __le64 base; >> + __le64 size; >> +}; >> + >> struct virtio_balloon { >> struct virtio_device *vdev; >> struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; >> @@ -67,6 +81,20 @@ struct virtio_balloon { >> >> /* Numbe...

...xtended chunks? IOW, why is the added complexity > of having two chunk formats worth it? You already reduced the overhead by > a factor of 4096 with normal chunks ... how often are extended chunks used > and how much more efficient are they than having several normal chunks? > Right, chunk_ext may be rarely used, thanks. I will remove chunk_ext if there is no objection from others. Best, Wei

...to free on OOM"); > @@ -50,6 +54,16 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); > static struct vfsmount *balloon_mnt; > #endif > > +struct balloon_page_chunk { > + __le64 base : 52; > + __le64 size : 12; > +}; > + > +struct balloon_page_chunk_ext { > + __le64 base; > + __le64 size; > +}; > + > struct virtio_balloon { > struct virtio_device *vdev; > struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > @@ -67,6 +81,20 @@ struct virtio_balloon { > > /* Number of balloon pages we've told the Host we...

...to free on OOM"); > @@ -50,6 +54,16 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); > static struct vfsmount *balloon_mnt; > #endif > > +struct balloon_page_chunk { > + __le64 base : 52; > + __le64 size : 12; > +}; > + > +struct balloon_page_chunk_ext { > + __le64 base; > + __le64 size; > +}; > + > struct virtio_balloon { > struct virtio_device *vdev; > struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; > @@ -67,6 +81,20 @@ struct virtio_balloon { > > /* Number of balloon pages we've told the Host we...

...S_IWUSR); MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); @@ -50,6 +54,16 @@ MODULE_PARM_DESC(oom_pages, "pages to free on OOM"); static struct vfsmount *balloon_mnt; #endif +struct balloon_page_chunk { + __le64 base : 52; + __le64 size : 12; +}; + +struct balloon_page_chunk_ext { + __le64 base; + __le64 size; +}; + struct virtio_balloon { struct virtio_device *vdev; struct virtqueue *inflate_vq, *deflate_vq, *stats_vq; @@ -67,6 +81,20 @@ struct virtio_balloon { /* Number of balloon pages we've told the Host we're not using. */ unsigned int num_pages; +...

Take over this work from Liang. This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 1) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Please check patch 0003 for more details about optimization 1). For an idle guest with 8GB RAM, optimization 2) can help shorten the total live migration

Take over this work from Liang. This patch series implements two optimizations: 1) transfer pages in chuncks between the guest and host; 1) transfer the guest unused pages to the host so that they can be skipped to migrate in live migration. Please check patch 0003 for more details about optimization 1). For an idle guest with 8GB RAM, optimization 2) can help shorten the total live migration

...e added complexity > > of having two chunk formats worth it? You already reduced the overhead by > > a factor of 4096 with normal chunks ... how often are extended chunks used > > and how much more efficient are they than having several normal chunks? > > > > Right, chunk_ext may be rarely used, thanks. I will remove chunk_ext if > there is no objection from others. > > Best, > Wei I don't think we can drop this, this isn't an optimization. One of the issues of current balloon is the 4k page size assumption. For example if you free a huge page yo...

...e added complexity > > of having two chunk formats worth it? You already reduced the overhead by > > a factor of 4096 with normal chunks ... how often are extended chunks used > > and how much more efficient are they than having several normal chunks? > > > > Right, chunk_ext may be rarely used, thanks. I will remove chunk_ext if > there is no objection from others. > > Best, > Wei I don't think we can drop this, this isn't an optimization. One of the issues of current balloon is the 4k page size assumption. For example if you free a huge page yo...