Re: Synchronization levels in SR

On Wed, 2010-05-26 at 13:03 +0900, Fujii Masao wrote:
> On Wed, May 26, 2010 at 1:04 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > On Tue, 2010-05-25 at 12:40 +0900, Fujii Masao wrote:
> >> On Tue, May 25, 2010 at 10:29 AM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
> >> > I agree that #4 should be done last, but it will be needed, not in the
> >> > least by your employer ;-) . I don't see any obvious way to make #4
> >> > compatible with any significant query load on the slave, but in general
> >> > I'd think that users of #4 are far more concerned with 0% data loss than
> >> > they are with getting the slave to run read queries.
> >>
> >> Since #2 and #3 are enough for 0% data loss, I think that such users
> >> would be more concerned about what results are visible in the standby.
> >> No?
> >
> > Please add #4 also. You can do that easily at the same time as #2 and
> > #3, and it will leave me free to fix the perceived conflict problems.
>
> I think that we should implement the feature in small steps rather than
> submit one big patch at a time. So I'd like to focus on #2 and #3 at first,
> and #4 later (maybe third or fourth CF).

We both know if you do #2 and #3 then doing #4 also is trivial.

If you leave it out then we'll end up missing something that is required
and have to rework everything.

--
Simon Riggs www.2ndQuadrant.com