<!-- MHonArc v2.4.4 --> <!--X-Subject: Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ?? --> <!--X-From-R13: X Q Znjerapr <pynjNhaqre.rate.ftv.pbz> --> <!--X-Date: Mon, 23 Mar 1998 21:42:40 +0000 --> <!--X-Message-Id: 199803232103.NAA53607#under,engr.sgi.com --> <!--X-Content-Type: text/plain --> <!--X-Reference: 9803230236.8w3d@ami-cg.GraySage.Edmonton.AB.CA --> <!--X-Head-End--> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <html> <head> <title>MUD-Dev message, Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</title> <!-- meta name="robots" content="noindex,nofollow" --> <link rev="made" href="mailto:claw#under,engr.sgi.com"> </head> <body background="/backgrounds/paperback.gif" bgcolor="#ffffff" text="#000000" link="#0000FF" alink="#FF0000" vlink="#006000"> <font size="+4" color="#804040"> <strong><em>MUD-Dev<br>mailing list archive</em></strong> </font> <br> [ <a href="../">Other Periods</a> | <a href="../../">Other mailing lists</a> | <a href="/search.php3">Search</a> ] <br clear=all><hr> <!--X-Body-Begin--> <!--X-User-Header--> <!--X-User-Header-End--> <!--X-TopPNI--> Date: [ <a href="msg00863.html">Previous</a> | <a href="msg00865.html">Next</a> ] Thread: [ <a href="msg00833.html">Previous</a> | <a href="msg00886.html">Next</a> ] Index: [ <A HREF="author.html#00864">Author</A> | <A HREF="#00864">Date</A> | <A HREF="thread.html#00864">Thread</A> ] <!--X-TopPNI-End--> <!--X-MsgBody--> <!--X-Subject-Header-Begin--> <H1>Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</H1> <HR> <!--X-Subject-Header-End--> <!--X-Head-of-Message--> <UL> <LI><em>To</em>: <A HREF="mailto:mud-dev#null,net">mud-dev#null,net</A></LI> <LI><em>Subject</em>: Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ?? </LI> <LI><em>From</em>: J C Lawrence <<A HREF="mailto:claw#under,engr.sgi.com">claw#under,engr.sgi.com</A>></LI> <LI><em>Date</em>: Mon, 23 Mar 1998 13:03:06 -0800</LI> </UL> <!--X-Head-of-Message-End--> <!--X-Head-Body-Sep-Begin--> <HR> <!--X-Head-Body-Sep-End--> <!--X-Body-of-Message--> <PRE> On Sun, 22 Mar 1998 23:27:30 PST8PDT Chris Gray<cg#ami-cg,GraySage.Edmonton.AB.CA> wrote: > - if multiple threads are updating the single image of the DB > (whether those threads are local or remote), then you need some kind > of consistency mechanism. If you use locks, then you are vulnerable > to a client vanishing when it holds locks - you will have to detect > that and rip the locks away. This also means that your execution > model has to be very complete with respect to locks, both read locks > and write locks. With remotely held locks, you can get some *very* > large latencies. Look at, umm, COOLMUD's distributed server model for a possible solution. It does rely on high-bandwidth low-latency connections between the relevant servers however. > Alternatively, you might try Chris L's lockless scheme, or > some variant. <bow> > If you use Chris L's lockless scheme, then after the thread > has run, you need to send full images of changed stuff back to the > server so that it can be compared and committed. Again, lots of > traffic and latency. Also, that C & C may take nearly as long as the > thread execution, so you end up losing out, in terms of the latency > seen by the user. This is true. What you really need is something like Arjuna's (or was that LINCKS -- sorry, its monday) distributed working set concept (forget what they call it), where objects migrate dynamically among the servers dependant on need and use characteristics. > A fully multithreaded server, using Chris L's C&C method, running on > a large multi-CPU SMP machine is likely the best way to get high > throughput. Agreed. You need the high speed interconnect support. SGI machines with HIPPI crossbars would probably also do in a depending on your load characteristics. -- J C Lawrence Internet: claw#null,net (Contractor) Internet: coder#ibm,net ---------(*) Internet: claw#under,engr.sgi.com ...Honourary Member of Clan McFud -- Teamer's Avenging Monolith... </PRE> <!--X-Body-of-Message-End--> <!--X-MsgBody-End--> <!--X-Follow-Ups--> <HR> <!--X-Follow-Ups-End--> <!--X-References--> <UL><LI><STRONG>References</STRONG>: <UL> <LI><STRONG><A NAME="00833" HREF="msg00833.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></STRONG> <UL><LI><EM>From:</EM> cg#ami-cg,GraySage.Edmonton.AB.CA (Chris Gray)</LI></UL></LI> </UL></LI></UL> <!--X-References-End--> <!--X-BotPNI--> <UL> <LI>Prev by Date: <STRONG><A HREF="msg00863.html">Re: [MUD-Dev] Jukebox</A></STRONG> </LI> <LI>Next by Date: <STRONG><A HREF="msg00865.html">Re: [MUD-Dev] Describe Concept</A></STRONG> </LI> <LI>Prev by thread: <STRONG><A HREF="msg00833.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></STRONG> </LI> <LI>Next by thread: <STRONG><A HREF="msg00886.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></STRONG> </LI> <LI>Index(es): <UL> <LI><A HREF="index.html#00864"><STRONG>Date</STRONG></A></LI> <LI><A HREF="thread.html#00864"><STRONG>Thread</STRONG></A></LI> </UL> </LI> </UL> <!--X-BotPNI-End--> <!--X-User-Footer--> <!--X-User-Footer-End--> <ul><li>Thread context: <BLOCKQUOTE><UL> <LI><STRONG>Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</STRONG>, <EM>(continued)</EM> <ul compact> <ul compact> <ul compact> <ul compact> <LI><strong><A NAME="00899" HREF="msg00899.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Vadim Tkachenko <a href="mailto:vt#freehold,crocodile.org">vt#freehold,crocodile.org</a>, Thu 26 Mar 1998, 01:59 GMT <UL> <LI><strong><A NAME="00904" HREF="msg00904.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Joel Dillon <a href="mailto:emily#cornholio,new.ox.ac.uk">emily#cornholio,new.ox.ac.uk</a>, Thu 26 Mar 1998, 15:52 GMT </LI> </UL> </LI> </ul> </ul> </ul> <LI><strong><A NAME="00830" HREF="msg00830.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Jon A. Lambert <a href="mailto:jlsysinc#ix,netcom.com">jlsysinc#ix,netcom.com</a>, Sun 22 Mar 1998, 21:10 GMT </LI> <LI><strong><A NAME="00833" HREF="msg00833.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Mon 23 Mar 1998, 06:54 GMT <UL> <LI><strong><A NAME="00864" HREF="msg00864.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, J C Lawrence <a href="mailto:claw#under,engr.sgi.com">claw#under,engr.sgi.com</a>, Mon 23 Mar 1998, 21:42 GMT </LI> <LI><strong><A NAME="00886" HREF="msg00886.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Vadim Tkachenko <a href="mailto:vt#freehold,crocodile.org">vt#freehold,crocodile.org</a>, Wed 25 Mar 1998, 05:28 GMT <UL> <LI><strong><A NAME="00902" HREF="msg00902.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Jon A. Lambert <a href="mailto:jlsysinc#ix,netcom.com">jlsysinc#ix,netcom.com</a>, Thu 26 Mar 1998, 05:03 GMT </LI> </UL> </LI> </UL> </LI> <LI><strong><A NAME="00836" HREF="msg00836.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Mon 23 Mar 1998, 07:07 GMT <UL> <LI><strong><A NAME="00839" HREF="msg00839.html">Re: [MUD-Dev] World Persistence, flat files v/s DB v/s ??</A></strong>, Ross Nicoll <a href="mailto:jrn#st-andrews,ac.uk">jrn#st-andrews,ac.uk</a>, Mon 23 Mar 1998, 08:09 GMT </LI> </UL> </LI> </ul> </LI> </UL></BLOCKQUOTE> </ul> <hr> <center> [ <a href="../">Other Periods</a> | <a href="../../">Other mailing lists</a> | <a href="/search.php3">Search</a> ] </center> <hr> </body> </html>