Re: BHYVE_SNAPSHOT

From: Warner Losh <imp_at_bsdimp.com>
Date: Mon, 01 May 2023 01:10:49 UTC
"Wow! That's eye popping"

On Sun, Apr 30, 2023, 6:46 PM Mario Marietto <marietto2008@gmail.com> wrote:

> whats the meaning of o_O ?
>
> Il lun 1 mag 2023, 02:04 Tomek CEDRO <tomek@cedro.info> ha scritto:
>
>> o_O
>>
>> --
>> CeDeROM, SQ7MHZ, http://www.tomek.cedro.info
>>
>> On Sun, Apr 30, 2023, 23:42 Matthew Grooms <mgrooms@shrew.net> wrote:
>>
>>> On 4/29/23 06:17, void wrote:
>>> > Hi,
>>> >
>>> > Where can I read up about the recently introduced BHYVE_SNAPSHOT ?
>>> >
>>> > I can only find terse information about what it does (in man 5
>>> src.conf)
>>> > but not about how to use it and/or why.
>>>
>>> This began as sponsored student work with the Politehnica University of
>>> Bucharest back in 2016 with an eye toward developing Live MIgration as a
>>> feature. The initial bhyve save/restore patch was committed back in 2020
>>> ...
>>>
>>> https://reviews.freebsd.org/rS360648
>>>
>>> Student projects related to bhyve continued until last year, but we gave
>>> up due to there being such a massive accumulation of patches with no
>>> path to getting them committed. We tried reaching out to project
>>> maintainers and the FreeBSD foundation alike for support and feedback,
>>> but there seems to be little to no interest. There have also been
>>> attempts by companies that rely on these features to and get them
>>> improved and committed. Unfortunately they don't appear to be having
>>> much luck either ...
>>>
>>> https://reviews.freebsd.org/D38858#885651
>>>
>>> Would you like to see support for VM snapshots in the generic kernel?
>>> How about support for saving/restore checkpoints using QCOW2, VMDK via
>>> libvdsk? How about support for warm or live migration? How about USB
>>> device pass-through? There are experimental patches for all these
>>> features that were developed by students at UPB. In a lot of cases,
>>> there are open reviews that have been waiting on feedback for ages. Here
>>> is a a presentation given by Elena from UPB just last month at the
>>> FreeBSD devsumit in Tokyo ...
>>>
>>>
>>> https://wiki.freebsd.org/DevSummit/202303?action=AttachFile&do=view&target=Presentation+-+bhyvecon.pdf
>>>
>>> The case is quite plain. I'm not sure what the solution is to this
>>> problem. I'd love to hear feedback from the community about how I've got
>>> this completely wrong and how the course could be corrected. That would
>>> be something.
>>>
>>> -Matthew
>>>
>>>
>>>
>>>