Re: [Gluster-devel] Gluster internals

[Ian Latter]

> > But they include an assumption.
> >
> > The query is: are async writes and reads sequential?  The
> > two specific cases are;
> >
> >  1) Are all reads that are initiated in time after a write
> >      guaranteed to occur after that write has taken affect?
> >
> 
> Yes
> 

Excellent.
 
> >
> >  2) Are all writes that are initiated in time after a write (x)
> >      guaranteed to occur after that write (x) has taken
> >      affect?
> >
> 
> Only overlapping offsets/regions retain causal ordering of completion. It
> is write-behind which acknowledges writes pre-maturely and therefore the
> layer which must maintain the 'effects' for further reads and writes by
> making the dependent IOs (overlapping offset/regions) wait for previous
> write's actual completion.
> 

Ok, that should do the trick.


Let me mull over this for a while .. Thanks for that info.


> Avati
> 


--
Ian Latter
Late night coder ..
http://midnightcode.org/