<div dir="ltr"><div class="gmail_extra">On Sat, Sep 7, 2013 at 10:38 AM, Florin Mateoc <span dir="ltr"><<a href="mailto:florin.mateoc@gmail.com" target="_blank">florin.mateoc@gmail.com</a>></span> wrote:<br><div class="gmail_quote">
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<pre>Hi Eliot,
> Eliot Miranda <<a href="http://lists.squeakfoundation.org/mailman/listinfo/vm-dev" target="_blank">eliot.miranda at gmail.com</a>> wrote:
>
> Hi Stéph,
>
> On Fri, Sep 6, 2013 at 9:35 AM, Stéphane Ducasse
> <<a href="http://lists.squeakfoundation.org/mailman/listinfo/vm-dev" target="_blank">stephane.ducasse at inria.fr</a>>wrote:
>
><i> Hi eliot
</i>>><i>
</i>><i>> This is really good that you write this blog. I read and I saw ephemerons
</i>><i>> (excellent because we were discussing them again today with esteban and
</i>><i>> igor)
</i>><i>> I have some questions that may be are stupid.
</i>><i>> - I was wondering if you plan to have a dedicated class space.
</i>><i>> Clement told me that in Chrome (but I may be wrong) they have that and in
</i>><i>> the class space the classes are not moved. But with the table you are sure
</i>><i>> that your index do not change so may be the gain is not important.
</i>>><i>
</i>>
> exactly.
Wouldn't a fixed, dedicated, class space facilitate though sharing between multiple images?
This was a nice feature in VW, and I think it may become even more important with the trend towards multi-core.
I also assume that a dedicated space for pinned memory might also simplify the garbage collector and even help performance a bit.
To me it appears that this kind of specialization of memory (splitting it into dedicated spaces) would almost always be a win.
While it increases the complexity by increasing the number of components to manage, it also simplifies the components, since they need to handle fewer special cases.
But I have never implemented a vm :)
I am also curious if you are including immediate floats in your 64-bit object format.
I am sure you know about it, but I saw this nice article about tagging in the current JavaScript implementations:
<a href="http://wingolog.org/archives/2011/05/18/value-representation-in-javascript-implementations" target="_blank">http://wingolog.org/archives/2011/05/18/value-representation-in-javascript-implementations</a></pre></div>
</blockquote><div><br></div><div>Yes, NaN-boxing is a good name for an old idea. Very cute. But I'm not going there. :-) Too much legacy, plus Smalltalk isn't JavaScript (JavaScript doesn't have integers except inside certain VMs).</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000"><pre>You only mentioned in your blog tagging for the 32-bit world (I think).
Can you please add some comments about 64-bit tagging?
Regards,
Florin<span class="Apple-style-span" style="font-family:arial;white-space:normal">-- </span></pre></div></blockquote></div>best,<div>Eliot</div>
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