Hi guys, Could you help to review this patch set? Thanks! Liang > -----Original Message----- > From: Li, Liang Z > Sent: Wednesday, December 21, 2016 2:52 PM > To: kvm@xxxxxxxxxxxxxxx > Cc: virtio-dev@xxxxxxxxxxxxxxxxxxxx; qemu-devel@xxxxxxxxxx; linux- > mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; virtualization@lists.linux- > foundation.org; amit.shah@xxxxxxxxxx; Hansen, Dave; > cornelia.huck@xxxxxxxxxx; pbonzini@xxxxxxxxxx; mst@xxxxxxxxxx; > david@xxxxxxxxxx; aarcange@xxxxxxxxxx; dgilbert@xxxxxxxxxx; > quintela@xxxxxxxxxx; Li, Liang Z > Subject: [PATCH v6 kernel 0/5] Extend virtio-balloon for fast (de)inflating & > fast live migration > > This patch set contains two parts of changes to the virtio-balloon. > > One is the change for speeding up the inflating & deflating process, the main > idea of this optimization is to use {pfn|length} to present the page > information instead of the PFNs, to reduce the overhead of virtio data > transmission, address translation and madvise(). This can help to improve the > performance by about 85%. > > Another change is for speeding up live migration. By skipping process guest's > unused pages in the first round of data copy, to reduce needless data > processing, this can help to save quite a lot of CPU cycles and network > bandwidth. We put guest's unused page information in a {pfn|length} array > and send it to host with the virt queue of virtio-balloon. For an idle guest with > 8GB RAM, this can help to shorten the total live migration time from 2Sec to > about 500ms in 10Gbps network environment. For an guest with quite a lot > of page cache and with little unused pages, it's possible to let the guest drop > it's page cache before live migration, this case can benefit from this new > feature too. > > Changes from v5 to v6: > * Drop the bitmap from the virtio ABI, use {pfn|length} only. > * Enhance the API to get the unused page information from mm. > > Changes from v4 to v5: > * Drop the code to get the max_pfn, use another way instead. > * Simplify the API to get the unused page information from mm. > > Changes from v3 to v4: > * Use the new scheme suggested by Dave Hansen to encode the bitmap. > * Add code which is missed in v3 to handle migrate page. > * Free the memory for bitmap intime once the operation is done. > * Address some of the comments in v3. > > Changes from v2 to v3: > * Change the name of 'free page' to 'unused page'. > * Use the scatter & gather bitmap instead of a 1MB page bitmap. > * Fix overwriting the page bitmap after kicking. > * Some of MST's comments for v2. > > Changes from v1 to v2: > * Abandon the patch for dropping page cache. > * Put some structures to uapi head file. > * Use a new way to determine the page bitmap size. > * Use a unified way to send the free page information with the bitmap > * Address the issues referred in MST's comments > > Liang Li (5): > virtio-balloon: rework deflate to add page to a list > virtio-balloon: define new feature bit and head struct > virtio-balloon: speed up inflate/deflate process > virtio-balloon: define flags and head for host request vq > virtio-balloon: tell host vm's unused page info > > drivers/virtio/virtio_balloon.c | 510 > ++++++++++++++++++++++++++++++++---- > include/linux/mm.h | 3 + > include/uapi/linux/virtio_balloon.h | 34 +++ > mm/page_alloc.c | 120 +++++++++ > 4 files changed, 621 insertions(+), 46 deletions(-) > > -- > 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html