Re: Pre-allocation of shared memory ...

Greg Stark wrote:
> I suspect this was less of an issue in the days before copy on write because
> vfork was more widely used/implemented. I'm not sure linux even implements
> vfork other than just as a wrapper around fork. Even BSD ditched it a while
> back though I think I saw that NetBSD reimplemented it since then.
>
> > But then there's the problem of people running database servers on
> > misconfigured machines. They should know better than not setting enough
> > swap space, IMHO anyway.
>
> Well, I've seen DBAs say "Since I don't want the database swapping anyways,
> I'll make really sure it doesn't swap by just not giving it any swap space --
> that's why we bought so much RAM in the first place". It's not obvious that
> you need swap to back memory the machine doesn't even report as being in
> use...

I see no reason RAM can't be used as backing store for possible
copy-on-write use.

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