Next Generation of Language
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From: Barry Margolin on 11 Jan 2007 00:04 In article <1168489207.874750.19330(a)77g2000hsv.googlegroups.com>, wv9557(a)yahoo.com wrote: > I don't think there is anything more anti parallelism like Lisp. Lisp > is recursive, a function has to basically wait for another instance of > itself to finish before continuing. Where is the parallelism? Functions like MAPCAR easily lend themselves to parallel variants that operate on many elements concurrently. *Lisp, the Lisp dialect for the massively-parallel Connection Machine, was built around operations like this. For coarse-grained parallelism, you can easily make use of the multi-threading features of most modern Lisps. -- Barry Margolin, barmar(a)alum.mit.edu Arlington, MA *** PLEASE post questions in newsgroups, not directly to me *** *** PLEASE don't copy me on replies, I'll read them in the group ***
From: Barry Margolin on 11 Jan 2007 00:23 In article <m3lkkba0bu.fsf(a)robohate.meer.net>, Madhu <enometh(a)meer.net> wrote: > * "Spiros Bousbouras" <1168298748.558477.152070(a)11g2000cwr.XXXXX.com> : > | If you want to analyse chess positions you can never > | have too much speed and it has nothing to do with > | rendering. I'm sure it's the same situation with go and > | many other games. > > But having more than one core will not be a benefit if your algorithms > are graph based and have to search a tree. IIRC most graph algorithms > (dfs bfs) are inherently unparallelizable. I think there was a Chess program for the Connection Machine, a massively parallel computer with thousands of very simple processors (or, in the case of the CM-5 model, hundreds of SPARC processors). I don't know the specifics of the algorithm, but my guess is that it worked by assigning analysis of different positions at a particular ply to each processor. Walking the tree isn't very parallelizable, but once you've reached the leaves you can get quite a bit of benefit. -- Barry Margolin, barmar(a)alum.mit.edu Arlington, MA *** PLEASE post questions in newsgroups, not directly to me *** *** PLEASE don't copy me on replies, I'll read them in the group ***
From: John Thingstad on 11 Jan 2007 01:16 On Thu, 11 Jan 2007 01:37:28 +0100, Robert Uhl <eadmund42(a)NOSPAMgmail.com> wrote: > "Tim Bradshaw" <tfb+google(a)tfeb.org> writes: >> >> However they do care about things like battery life, noise, and system >> cost which correlate quite well with power consumption. And they >> *will* care about power consumption (even the Americans) when the >> systems start costing significantly more than their purchase cost to >> run for a year. > > How long until that's the case? I just built a new box with a Pentium D > (said box is never turned off, ever), and the gas & electricity bill for > my entire home is still around $40-$60/month, depending on the season of > the year. And I'm a homebrewer, which means that I spend a significant > amount of electricity heating 6 1/2 gallons of liquid and boiling it > down to 5 1/4 gallons. Oh, and it's winter here in Denver, so I have to > heat my home. > Well modern computers come with power saving features. Max consumption on my machine is about 400 W. For a machine with dual graphics boards consumption can be as high as 1000 W. But average consumption is much lower, more like 40 W. So about as much as a light-bulb. -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/
From: Juan R. on 11 Jan 2007 04:07 Pascal Bourguignon ha escrito: > > Neural Networks, > > > > To what end? > > To do your job in your place. In ten years, we'll have enough > processing power and memory in desktop computers to modelize a whole > human brain. Better have parallal processors then, if you want to > emulate one at an acceptable speed. >From where did you get that data? So far as i know the prediction is that at some time in the second half of this century, fast supercomputer could only offers us a 1000s MD simulation for a _E. coli_ (~ 10^10 heavy atoms). MD simulations are very inexpensive and rough. Prediction suggests no accurate _ab initio_ model would be available on this century.
From: John Thingstad on 11 Jan 2007 04:19
On Thu, 11 Jan 2007 10:07:12 +0100, Juan R. <juanrgonzaleza(a)canonicalscience.com> wrote: > > Pascal Bourguignon ha escrito: > >> > Neural Networks, >> > >> > To what end? >> >> To do your job in your place. In ten years, we'll have enough >> processing power and memory in desktop computers to modelize a whole >> human brain. Better have parallal processors then, if you want to >> emulate one at an acceptable speed. > >> From where did you get that data? > > So far as i know the prediction is that at some time in the second half > of this century, fast supercomputer could only offers us a 1000s MD > simulation for a _E. coli_ (~ 10^10 heavy atoms). MD simulations are > very inexpensive and rough. Prediction suggests no accurate _ab initio_ > model would be available on this century. > My suggestion is to forget Moor's law. Computing increase in power increase has been decreasing for some time. Growth is no longer exponential but scalar. Say, a quad core CPU has 180% the speed of a single core. Amdahl's law (wikipedia) -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/ |