Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread Pankaj Gupta
> > I mean, that would be fundamentally broken, because the fsync() would > > corrupt the file. So I assume in a sane environment, the dst could only > > have stale clean pagecache pages. And we'd have to get rid of these to > > re-read everything from file. > > >>> > > >>> In c

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread Pankaj Gupta
> I mean, that would be fundamentally broken, because the fsync() would > corrupt the file. So I assume in a sane environment, the dst could only > have stale clean pagecache pages. And we'd have to get rid of these to > re-read everything from file. > >>> > >>> In case of write

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread David Hildenbrand
On 12.01.22 17:08, Pankaj Gupta wrote: I mean, that would be fundamentally broken, because the fsync() would corrupt the file. So I assume in a sane environment, the dst could only have stale clean pagecache pages. And we'd have to get rid of these to re-read everything from fil

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread Pankaj Gupta
> >> I mean, that would be fundamentally broken, because the fsync() would > >> corrupt the file. So I assume in a sane environment, the dst could only > >> have stale clean pagecache pages. And we'd have to get rid of these to > >> re-read everything from file. > > > > In case of write back cache

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread Pankaj Gupta
Thank you David for replying! > > From: Pankaj Gupta > > > > > Enable live migration support for virtio-pmem device. > > Tested this: with live migration on same host. > > > > Need suggestion on below points to support virtio-pmem live migration > > between two separate host systems: > > I assume

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread David Hildenbrand
>> >> I mean, that would be fundamentally broken, because the fsync() would >> corrupt the file. So I assume in a sane environment, the dst could only >> have stale clean pagecache pages. And we'd have to get rid of these to >> re-read everything from file. > > In case of write back cache mode, we

Re: [RFC] virtio_pmem: enable live migration support

2022-01-12 Thread David Hildenbrand
On 31.12.21 13:01, Pankaj Gupta wrote: > From: Pankaj Gupta > > > Enable live migration support for virtio-pmem device. > Tested this: with live migration on same host. > > Need suggestion on below points to support virtio-pmem live migration > between two separate host systems: I assume emulate

[RFC] virtio_pmem: enable live migration support

2021-12-31 Thread Pankaj Gupta
From: Pankaj Gupta > Enable live migration support for virtio-pmem device. Tested this: with live migration on same host. Need suggestion on below points to support virtio-pmem live migration between two separate host systems: - There is still possibility of stale page cache page at the destin