similar to: [RFC for Linux] virtio_balloon: Add VIRTIO_BALLOON_F_THP_ORDER to handle THP spilt issue

On Thu, Apr 02, 2020 at 04:00:05PM +0800, teawater wrote: > > > > 2020?3?31? 22:07?Michael S. Tsirkin <mst at redhat.com> ??? > > > > On Tue, Mar 31, 2020 at 04:03:18PM +0200, David Hildenbrand wrote: > >> On 31.03.20 15:37, Michael S. Tsirkin wrote: > >>> On Tue, Mar 31, 2020 at 03:32:05PM +0200, David Hildenbrand wrote: > >>>>

On 31.03.20 18:27, Nadav Amit wrote: >> On Mar 31, 2020, at 6:32 AM, David Hildenbrand <david at redhat.com> wrote: >> >> On 31.03.20 15:24, Michael S. Tsirkin wrote: >>> On Tue, Mar 31, 2020 at 12:35:24PM +0200, David Hildenbrand wrote: >>>> On 26.03.20 10:49, Michael S. Tsirkin wrote: >>>>> On Thu, Mar 26, 2020 at 08:54:04AM +0100,

On 12.03.20 08:49, Hui Zhu wrote: > If the guest kernel has many fragmentation pages, use virtio_balloon > will split THP of QEMU when it calls MADV_DONTNEED madvise to release > the balloon pages. > This is an example in a VM with 1G memory 1CPU: > cat /proc/meminfo | grep AnonHugePages: > AnonHugePages: 0 kB > > usemem --punch-holes -s -1 800m & > >

On 12.03.20 08:49, Hui Zhu wrote: > If the guest kernel has many fragmentation pages, use virtio_balloon > will split THP of QEMU when it calls MADV_DONTNEED madvise to release > the balloon pages. > This is an example in a VM with 1G memory 1CPU: > cat /proc/meminfo | grep AnonHugePages: > AnonHugePages: 0 kB > > usemem --punch-holes -s -1 800m & > >

On Thu, Mar 12, 2020 at 03:49:54PM +0800, Hui Zhu wrote: > If the guest kernel has many fragmentation pages, use virtio_balloon > will split THP of QEMU when it calls MADV_DONTNEED madvise to release > the balloon pages. > This is an example in a VM with 1G memory 1CPU: > cat /proc/meminfo | grep AnonHugePages: > AnonHugePages: 0 kB > > usemem --punch-holes -s -1

On Thu, Mar 12, 2020 at 09:37:32AM +0100, David Hildenbrand wrote: > 2. You are essentially stealing THPs in the guest. So the fastest > mapping (THP in guest and host) is gone. The guest won't be able to make > use of THP where it previously was able to. I can imagine this implies a > performance degradation for some workloads. This needs a proper > performance evaluation. I

Introduce interfaces for ballooning enqueueing and dequeueing of a list of pages. These interfaces reduce the overhead of storing and restoring IRQs by batching the operations. In addition they do not panic if the list of pages is empty. Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc: Jason Wang <jasowang at redhat.com> Cc: linux-mm at kvack.org Cc: virtualization at

Introduce interfaces for ballooning enqueueing and dequeueing of a list of pages. These interfaces reduce the overhead of storing and restoring IRQs by batching the operations. In addition they do not panic if the list of pages is empty. Cc: Jason Wang <jasowang at redhat.com> Cc: linux-mm at kvack.org Cc: virtualization at lists.linux-foundation.org Acked-by: Michael S. Tsirkin <mst at

On Wed, Feb 06, 2019 at 03:57:03PM -0800, Nadav Amit wrote: > Introduce interfaces for ballooning enqueueing and dequeueing of a list > of pages. These interfaces reduce the overhead of storing and restoring > IRQs by batching the operations. In addition they do not panic if the > list of pages is empty. > > Cc: "Michael S. Tsirkin" <mst at redhat.com> > Cc:

On Thu, Mar 28, 2019 at 01:07:15AM +0000, Nadav Amit wrote: > Introduce interfaces for ballooning enqueueing and dequeueing of a list > of pages. These interfaces reduce the overhead of storing and restoring > IRQs by batching the operations. In addition they do not panic if the > list of pages is empty. > > Cc: "Michael S. Tsirkin" <mst at redhat.com> > Cc:

On Tue, Apr 23, 2019 at 04:45:28PM -0700, Nadav Amit wrote: > Introduce interfaces for ballooning enqueueing and dequeueing of a list > of pages. These interfaces reduce the overhead of storing and restoring > IRQs by batching the operations. In addition they do not panic if the > list of pages is empty. > > Cc: "Michael S. Tsirkin" <mst at redhat.com> > Cc:

On Fri, Apr 19, 2019 at 10:34:04PM +0000, Nadav Amit wrote: > > On Apr 19, 2019, at 3:07 PM, Michael S. Tsirkin <mst at redhat.com> wrote: > > > > On Thu, Mar 28, 2019 at 01:07:15AM +0000, Nadav Amit wrote: > >> Introduce interfaces for ballooning enqueueing and dequeueing of a list > >> of pages. These interfaces reduce the overhead of storing and

Lots of comments bitrotted. Fix them up. Fixes: 418a3ab1e778 (mm/balloon_compaction: List interfaces) Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- mm/balloon_compaction.c | 73 +++++++++++++++++++++++------------------ 1 file changed, 41 insertions(+), 32 deletions(-) diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index d25664e1857b..9cb03da5bcea 100644 ---

Lots of comments bitrotted. Fix them up. Fixes: 418a3ab1e778 (mm/balloon_compaction: List interfaces) Reviewed-by: Wei Wang <wei.w.wang at intel.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- fixes since v3: teaks suggested by Wei mm/balloon_compaction.c | 71 ++++++++++++++++++++++------------------- 1 file changed, 39 insertions(+), 32 deletions(-) diff --git

On Thu, Mar 12, 2020 at 03:49:55PM +0800, Hui Zhu wrote: > If the guest kernel has many fragmentation pages, use virtio_balloon > will split THP of QEMU when it calls MADV_DONTNEED madvise to release > the balloon pages. > Set option thp-order to on will open flags VIRTIO_BALLOON_F_THP_ORDER. > It will set balloon size to THP size to handle the THP split issue. > >

From: "Michael S. Tsirkin" <mst.redhat.com> fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(),

fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to serialize

fill_balloon doing memory allocations under balloon_lock can cause a deadlock when leak_balloon is called from virtballoon_oom_notify and tries to take same lock. To fix, split page allocation and enqueue and do allocations outside the lock. Here's a detailed analysis of the deadlock by Tetsuo Handa: In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to serialize

"Michael S. Tsirkin" <mst at redhat.com> writes: > fill_balloon doing memory allocations under balloon_lock > can cause a deadlock when leak_balloon is called from > virtballoon_oom_notify and tries to take same lock. > > To fix, split page allocation and enqueue and do allocations outside the lock. > > Here's a detailed analysis of the deadlock by Tetsuo

On Fri, Dec 01, 2017 at 11:31:08PM +1100, Michael Ellerman wrote: > "Michael S. Tsirkin" <mst at redhat.com> writes: > > > fill_balloon doing memory allocations under balloon_lock > > can cause a deadlock when leak_balloon is called from > > virtballoon_oom_notify and tries to take same lock. > > > > To fix, split page allocation and enqueue and