Re: [Qemu-devel] [PATCH V8 3/5] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()

2019-01-14 Thread Michael S. Tsirkin
On Tue, Jan 15, 2019 at 10:49:45AM +0800, Yi Zhang wrote: > On 2019-01-14 at 17:07:02 -0200, Eduardo Habkost wrote: > > On Wed, Jan 02, 2019 at 01:26:15PM +0800, Zhang Yi wrote: > > > When a file supporting DAX is used as vNVDIMM backend, mmap it with > > > MAP_SYNC flag in addition which can ensur

Re: [Qemu-devel] [PATCH V8 3/5] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()

2019-01-14 Thread Yi Zhang
On 2019-01-14 at 17:07:02 -0200, Eduardo Habkost wrote: > On Wed, Jan 02, 2019 at 01:26:15PM +0800, Zhang Yi wrote: > > When a file supporting DAX is used as vNVDIMM backend, mmap it with > > MAP_SYNC flag in addition which can ensure file system metadata > > synced in each guest writes to the back

Re: [Qemu-devel] [PATCH V8 3/5] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()

2019-01-14 Thread Eduardo Habkost
On Wed, Jan 02, 2019 at 01:26:15PM +0800, Zhang Yi wrote: > When a file supporting DAX is used as vNVDIMM backend, mmap it with > MAP_SYNC flag in addition which can ensure file system metadata > synced in each guest writes to the backend file, without other QEMU > actions (e.g., periodic fsync() b

[Qemu-devel] [PATCH V8 3/5] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()

2019-01-01 Thread Zhang Yi
When a file supporting DAX is used as vNVDIMM backend, mmap it with MAP_SYNC flag in addition which can ensure file system metadata synced in each guest writes to the backend file, without other QEMU actions (e.g., periodic fsync() by QEMU). Signed-off-by: Haozhong Zhang Signed-off-by: Zhang Yi