[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Gluster-devel] Gluster internals
From: |
Ian Latter |
Subject: |
Re: [Gluster-devel] Gluster internals |
Date: |
Tue, 22 May 2012 17:18:08 +1000 |
> > 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/