[Sheepdog] [PATCH 1/2] sheep: sheep: handle node change event first

[MORITA Kazutaka]

At Sun, 01 Apr 2012 15:30:20 +0800,
Liu Yuan wrote:
> 
> On 04/01/2012 11:41 AM, MORITA Kazutaka wrote:
> 
> > Let's take another approach.  Here is my suggestion:
> > 
> >  - Use different queues for I/O requests and membership events.
> >  - When membership queue is empty, we can process I/O requests as
> >    usual.
> >  - When membership queue is not empty, flush all outstanding I/Os.
> >    New I/O requests are blocked until the membership queue becomes
> >    empty.
> 
> 
> Let's leave aside IO req that are just queued, not issued.
> 
> Even with separate queues, seems that we need to wait for completion of
> infly IOs. No?

Yes.

> 
> So one queue with higher priority placement of notify & confchg event,
> we could have a working solution.

Yes, I guess it will work.  I thought it is simpler to use two queues
than traversing one queue to find the proper placement, though.

Thanks,

Kazutaka