On 12/08/2012 05:27 PM, Darren New wrote:
> On 8/12/2012 2:23, Orchid Win7 v1 wrote:
>> I like how the algorithm description is sufficiently vague that you can't
>> tell how it actually works.
>
> It was four clicks away, with the previous three clicks giving
> successively more detailed descriptions.
>
> http://labs.oracle.com/jtech/pubs/04-g1-paper-ismm.pdf
>
> You're welcome.

No.

This is the GC from Sun, the GC that the Azul one is supposed to be 
superior to.

>> it "detects" any attempt to access a moved object, but again doesn't say
>> how.
>
> Memory mapping. It traps on reading the memory that hasn't been fixed
> yet, then fixed up the entire page worth of references, then marks the
> memory as readable.

So you mean it relocates an entire page of live objects, and then uses 
page faults to detect access to the non-existent page and lookup where 
the data has gone?

The only problem with that, of course, is that paging is controlled by 
the operating system, not by a user-level application program.

>> Since it's impossible to have a machine with 140GB of RAM,
>
> Since when is it impossible? We had 128G of RAM on the Sparcstation we
> used back in 1995 or so. And that wasn't even a mainframe.

That's interesting. Because in 1998, I did some work experience with BT. 
One day I was showed into their main datacenter, and their most powerful 
server was running off a RAID-5 array containing not one, not two, not 
three, but SEVEN 4.2 GB drives. I remember feeling slightly giddy trying 
to work out how many multiple gigabytes of data that thing must be able 
to hold in total.

And you're claiming you had 100x more than that IN RAM? Somehow, I doubt it.

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