Re: WAL & SHM principles

> > > Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > > > The only problem is that we would no longer have control over which
> > > > pages made it to disk. The OS would perhaps write pages as we modified
> > > > them. Not sure how important that is.
> > >
> > > Unfortunately, this alone is a *fatal* objection. See nearby
> > > discussions about WAL behavior: we must be able to control the relative
> > > timing of WAL write/flush and data page writes.
> >
> > Bummer.
> >
> BTW, what means "bummer" ?

Sorry, it means, "Oh, I am disappointed."

> But for many OSes you CAN control when to write data - you can mlock
> individual pages.

mlock() controls locking in physical memory. I don't see it controling
write().

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