Code of current version for Linux and qemu is available in [1] and [2]. Update of this version: 1. Report continuous pages will increase the speed. So added deflate continuous pages. 2. According to the comments from David in [3], added 2 new vqs icvq and dcvq to get continuous pages with format 32 bits pfn and 32 bits size.
Following is the introduction of the function. Set option cont-pages to on will open flags VIRTIO_BALLOON_F_CONT_PAGES. qemu will get continuous pages from icvq and dcvq and do madvise MADV_WILLNEED and MADV_DONTNEED with the pages. Opening this flag can bring two benefits: 1. Increase the speed of balloon inflate and deflate. 2. Decrease the splitted THPs number in the host. [1] https://github.com/teawater/linux/tree/balloon_conts [2] https://github.com/teawater/qemu/tree/balloon_conts [3] https://lkml.org/lkml/2020/5/13/1211 Hui Zhu (2): virtio_balloon: Add cont-pages and icvq virtio_balloon: Add dcvq to deflate continuous pages hw/virtio/virtio-balloon.c | 92 +++++++++++++++--------- include/hw/virtio/virtio-balloon.h | 2 include/standard-headers/linux/virtio_balloon.h | 1 3 files changed, 63 insertions(+), 32 deletions(-)
