Re: Restore-reliability mode

Noah Misch wrote:
> On Thu, Jul 23, 2015 at 04:53:49PM -0300, Alvaro Herrera wrote:
> > Peter Geoghegan wrote:
> > > On Sat, Jun 6, 2015 at 12:58 PM, Noah Misch <noah(at)leadboat(dot)com> wrote:
> > > > - Call VALGRIND_MAKE_MEM_NOACCESS() on a shared buffer when its local pin
> > > > count falls to zero. Under CLOBBER_FREED_MEMORY, wipe a shared buffer
> > > > when its global pin count falls to zero.
> > >
> > > Did a patch for this ever materialize?
> >
> > I think the first part would be something like the attached.
>
> Neat. Does it produce any new complaints during "make installcheck"?

I only tried a few tests, for lack of time, and it didn't produce any.
(To verify that the whole thing was working properly, I reduced the
range of memory made available during PinBuffer and that resulted in a
crash immediately). I am not really familiar with valgrind TBH and just
copied a recipe to run postmaster under it, so if someone with more
valgrind-fu could verify this, it would be great.

This part:

> > > > Under CLOBBER_FREED_MEMORY, wipe a shared buffer when its
> > > > global pin count falls to zero.

can be done without any valgrind, I think. Any takers?

--
Álvaro Herrera http://www.2ndQuadrant.com/
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