Messages in this thread | | | Subject | Re: [Devel] Re: [PATCH 0/9] OpenVZ kernel based checkpointing/restart | From | Dave Hansen <> | Date | Thu, 30 Oct 2008 10:03:35 -0700 |
| |
On Thu, 2008-10-30 at 10:02 +0400, Andrey Mirkin wrote: > Anyway we should ask everyone what they think about user- and kernel- based > process creation. > Dave, Serge, Cedric, Daniel, Louis what do you think about that?
My worry is where a single sys_restart() plus in-kernel process creation takes us.
In practice, what do we do? Do we single-thread the entire restore process? Or, do we do in-kernel process creation and have multiple kernel threads trying to read out of different points in the checkpoint file, trying to restore all their own states in parallel? Does that mean that we can't in practice restore from a fd like a pipe or a network socket?
In the same way, if we *do* create the processes in userspace, how do we do _that_? Do we just fork() and sleep() until the kernel comes along and blows our state away? How does the kernel process doing the restoring tell userspace how many things to fork? How do we match these new userspace processes up with the ones coming out of the checkpoint process?
To me, it's just way too early to talk about this stuff. Both approaches have their issues, and I'm yet to see the differences manifested in code so I can really sink my teeth into them
-- Dave
| |