Re: WAL & SHM principles

> > > Bruce Momjian <pgman@candle.pha.pa.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().

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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