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<H1>Re: [MUD-Dev] ColdStore</H1>
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<LI><em>To</em>: <A HREF="mailto:mud-dev#kanga,nu">mud-dev#kanga,nu</A></LI>
<LI><em>Subject</em>: Re: [MUD-Dev] ColdStore</LI>
<LI><em>From</em>: Cynbe ru Taren &lt;<A HREF="mailto:cynbe#muq,org">cynbe#muq,org</A>&gt;</LI>
<LI><em>Date</em>: Wed, 8 Dec 1999 15:46:51 -0600</LI>
<LI><em>Reply-To</em>: <A HREF="mailto:mud-dev#kanga,nu">mud-dev#kanga,nu</A></LI>
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<PRE>

Miroslav Silovic &lt;silovic#zesoi,fer.hr&gt; wrote:

| J C Lawrence &lt;claw#kanga,nu&gt; writes:
| &gt; ColdStore is a gigabyte-scale persistent object store ...
|
| Ok, I did more extensive research into this (mostly because I know the
| authors).

Thank you for a very informative post!

I've been watching ColdStore out of the corner of my eye
without having had time to take a serious look at it.

I'm particularly interested because I'm planning on converting
Muq to using mmap() next year.  Your comments suggest that
perhaps I should retain the ability to run non-mmap()ed when I do.



| With mmap, you're limited to the largest contiguous segment in
| your address space, which really is about 1 gb on most OSes.

Did you mean "most 32-bit OSes"?

I don't mean to carp, but outside of Intel x86 boxes, 32-bits
seems basically dead, and I'd presumed that the 64-bit world
was roomier than this?



|  - bug recovery is nonexistent. If your broken C++ code hits mmaped
| memory, you can say goodbye to the entire db.

You obviously have alternatives in mind, but they aren't clear to
me.

I'd guess broken C++ code hitting memory could in principle trash
any db, but you see the risks as several orders of magnitude greater
when the entire db is memory-mapped, vs just a cache of it?

Or do you have solutions in mind for doing bug recovery well in
mmap()ed implementations, which ColdStore merely isn't implementing?



|  - db format is highly non-portable. It's not just architecture
| dependant, it's C++ compiler dependant (as object layout may change).

Is the db format COFF?  Or what was the relationship to COFF?  Or
am I misunderstanding completely some of the ColdStore-related
traffic I vaguely remember?



| BTW, has there been any discussion on the list on incremental/generational
| GC? (that works best for MUDs by far, IMHO - you can really bump up your
| realtime response once you implement incrementality properly).

You sound knowledgable:  I'd be interested to hear you comment further.

In Muq, I'm currently using a plain-jane mark-and-sweep monolithic
gc I hacked together one weekend just to have something rather than
nothing.

I've been contemplating going to a two-generation system and/or
implementing Dijkstra's three-color incremental algorithm.

(I believe Muq's architecture, based on soft pointers indirected
through in essence a software MMU, should make Dijkstra's algorithm
particularly easy to implement.)

Is there prior mud art with other approaches?  Are there working
systems or good references I should be boning up on before proceeding?



Once again, thanks for taking time to make a very informative post!

  Cynbe



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<li><strong><A NAME="00562" HREF="msg00562.html">Re: [MUD-Dev] ColdStore</A></strong>
<ul compact><li><em>From:</em> Miroslav Silovic &lt;silovic@zesoi.fer.hr&gt;</li></ul>
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<ul><li>Thread context:
<BLOCKQUOTE><UL>
<LI><STRONG>Re: [MUD-Dev] New AI Engine released</STRONG>, <EM>(continued)</EM>
<ul compact>
<LI><strong><A NAME="00576" HREF="msg00576.html">Re: [MUD-Dev] New AI Engine released</A></strong>, 
Elysium <a href="mailto:tear@ministryofsound.net">tear@ministryofsound.net</a>, Fri 10 Dec 1999, 02:32 GMT
</LI>
<LI><strong><A NAME="00566" HREF="msg00566.html">Re: [MUD-Dev] New AI Engine released</A></strong>, 
Bruce Mitchener, Jr. <a href="mailto:bruce@puremagic.com">bruce@puremagic.com</a>, Thu 09 Dec 1999, 17:05 GMT
</LI>
</ul>
</LI>
<LI><strong><A NAME="00545" HREF="msg00545.html">[MUD-Dev] ColdStore</A></strong>, 
J C Lawrence <a href="mailto:claw@kanga.nu">claw@kanga.nu</a>, Wed 08 Dec 1999, 19:30 GMT
<UL>
<LI><strong><A NAME="00546" HREF="msg00546.html">Re: [MUD-Dev] ColdStore</A></strong>, 
Miroslav Silovic <a href="mailto:silovic@zesoi.fer.hr">silovic@zesoi.fer.hr</a>, Wed 08 Dec 1999, 20:28 GMT
</LI>
</UL>
<UL>
<li>&lt;Possible follow-up(s)&gt;<br>
<LI><strong><A NAME="00552" HREF="msg00552.html">Re: [MUD-Dev] ColdStore</A></strong>, 
Cynbe ru Taren <a href="mailto:cynbe@muq.org">cynbe@muq.org</a>, Wed 08 Dec 1999, 21:48 GMT
<UL>
<LI><strong><A NAME="00562" HREF="msg00562.html">Re: [MUD-Dev] ColdStore</A></strong>, 
Miroslav Silovic <a href="mailto:silovic@zesoi.fer.hr">silovic@zesoi.fer.hr</a>, Thu 09 Dec 1999, 12:07 GMT
<UL>
<LI><strong><A NAME="00563" HREF="msg00563.html">Re: [MUD-Dev] ColdStore</A></strong>, 
J C Lawrence <a href="mailto:claw@kanga.nu">claw@kanga.nu</a>, Thu 09 Dec 1999, 12:43 GMT
</LI>
</UL>
</LI>
</UL>
</LI>
</UL>
</LI>
<LI><strong><A NAME="00543" HREF="msg00543.html">[MUD-Dev] Scenarios</A></strong>, 
Chris Lloyd <a href="mailto:crl199@soton.ac.uk">crl199@soton.ac.uk</a>, Tue 07 Dec 1999, 23:54 GMT
<LI><strong><A NAME="00526" HREF="msg00526.html">[MUD-Dev] New member</A></strong>, 
IronWolf <a href="mailto:ironwolf@ewa.net">ironwolf@ewa.net</a>, Mon 06 Dec 1999, 06:10 GMT
</UL></BLOCKQUOTE>

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