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Submission + - Extreme Memory Oversubscription for VMs (gridcentriclabs.com) 4

Laxitive writes: Virtualization systems currently have a pretty easy time oversubscribing CPUs (running lots of VMs on a few CPUs), but have had a very hard time oversubscribing memory. GridCentric, a virtualization startup, just posted on their blog a video demoing the creation of 16 one-gigabyte desktop VMs (running X) on a computer with just 5 gigs of ram. The blog post includes a good explanation of how this is accomplished, along with a description of how it's different from the major approaches being used today (memory ballooning, VMWare's page sharing, etc.). Their method is based on a combination of lightweight VM cloning (sort of like fork() for VMs) and on-demand paging. Seems like the 'other half' of resource oversubscription for VMs might finally be here.

Comment Re:new? (Score 2, Insightful) 278

It's not that 3d user interfaces have been fully explored, but that simulated 3d interfaces on 2d desktops have some fundamental limitations. We already have some amount of simulated pseudo-depth: windows can lie on top of other windows, etc.

The problem is that by the time you get around to interacting with something, you're interacting with a 2d euclidean plane which presents a projection of some 3d model. It doesn't make the plane 3d. You can't reach around and touch the "middle" of an 3d object projected onto a 2d plane. That's a problem. These might be somewhat ameliorated by true 3d interfaces (where the display itself is 3d), but that tech has yet to mature.

If you think about it, even the way we work on our typical desk is mostly 2d, from a topological perspective. I have a pile of papers and some random crap lying around my desk. When I go to grab a document to work on, I don't just reach into the middle of a stack and pull out the right one. I don't have that capability. I need to go and start flipping pages, basically morphing my 2d topology to reveal some object hidden in 3d, and only then interact with it.

That's not to say that all 3d effects and stuff are useless. Simulated 3d is a great way of providing visual cues that we have been training ourselves on since we opened our eyes. That can be a very important aspect of intuitive interfaces.. but fundamentally it acts as a visual highlight. The goodness or badness of any particular 3d interface depends entirely on how effectively the _2d_ projection is.

Thirdly, "true" 3d is actually too limiting. We are forced to live in a 3d world, but our computers give us access to many more dimensions, weirder dimensions, than that. We can provide 2d projections of abstract non-fixed-dimensional objects, like n-ary trees (e.g. filesystems). An example of a projection of that abstract object to a 2d interface would be spotlight. It provides a 2d textbox which behaves in strange and weird ways - a 2d textbox that projects 2d manipulations (type some characters), into an arbitrary traversal of the tree. Compare the utility of that to the utility of a "true" 3d rendered filesystem. What value would that add? Sure, it would look neat, but what extra thing would you gain from it?

There's nothing magic about 3d. Computers operate above and beyond limitations of 3 dimensions, and are currently constrained to expose their behaviour through primarily 2d interfaces. Simulating 3d on top of 2d user interfaces, aside from the "visual cue" aspect, is kind of an arbitrary choice.. not necessarily the best one.

-Laxitive

Comment Re:India is sooo into equality (Score 1) 204

Ah, I see, you must be referring to the Delhi high court's support of caste discrimination. I'm having a bit of trouble finding examples of that, though. Could you point me to some of your examples?

I tried searching for '...' in google, but it doesn't yield too much in the way of results relating to the delhi high court.

Thanks in advance!

-Laxitive

Comment Re:India is sooo into equality (Score 2, Insightful) 204

I'm sure if you lend the Indians your time machine, they can go back in time and fix that issue. Until then, I guess they'll have to just live with outlawing caste discrimination in the constitution and then slowly working to change public attitudes.

Or perhaps you've discovered a way to fix the issue with smug off-topic one-liners?

Do tell. I eagerly await your insight into the issue.

-Laxitive

Comment Re:re Increase or decline? (Score 4, Insightful) 746

In experimental science, this is not uncommon. Using different methods of analyzing the same subject is, in other words, using (relatively) independent methods to analyze that subject. Using multiple independent methods and combining their results is a good thing, because it avoids experimental error and potential systemic biases that exist in every observational setup.

That said, I don't want to get into an actual discussion about the actual paper in question because I have not read the relevant hacked personal e-mails with their full context and interpreted their significance (and I likely won't have time in the near future given the pressures of day to day life). I am not particularly inclined to start implying conclusions and accusations based off of an incomplete and shoddy reading of a few out-of-context paragraphs. I am neither willing to vouch for or defend, or attack a particular piece of research until I am reasonably well informed about how that research was conducted.

There seem to be many people, however, who are willing to do exactly that.

-Laxitive

Comment Re:re Increase or decline? (Score 5, Insightful) 746

Response from the RealClimate website, here (http://www.realclimate.org/index.php/archives/2009/11/the-cru-hack/#more-1853):

No doubt, instances of cherry-picked and poorly-worded “gotcha” phrases will be pulled out of context. One example is worth mentioning quickly. Phil Jones in discussing the presentation of temperature reconstructions stated that “I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline.” The paper in question is the Mann, Bradley and Hughes (1998) Nature paper on the original multiproxy temperature reconstruction, and the ‘trick’ is just to plot the instrumental records along with reconstruction so that the context of the recent warming is clear. Scientists often use the term “trick” to refer to a “a good way to deal with a problem”, rather than something that is “secret”, and so there is nothing problematic in this at all. As for the ‘decline’, it is well known that Keith Briffa’s maximum latewood tree ring density proxy diverges from the temperature records after 1960 (this is more commonly known as the “divergence problem”–see e.g. the recent discussion in this paper) and has been discussed in the literature since Briffa et al in Nature in 1998 (Nature, 391, 678-682). Those authors have always recommend not using the post 1960 part of their reconstruction, and so while ‘hiding’ is probably a poor choice of words (since it is ‘hidden’ in plain sight), not using the data in the plot is completely appropriate, as is further research to understand why this happens.

This will indeed cause certain people to "wonder". Especially people who do not have the faculties to properly understand the idiomatic uses of the English language, and people who are willing to take words and phrases of out of context, as well as people who are willing to formulate their opinions without considering the actual analysis and instead relying on secondhand hysteria generated by others who are also not willing to consider the actual analysis.

So it goes.

-Laxitive

Comment Re:Cynicism (Score 5, Insightful) 90

If you think that fast and cheap DNA reading applies only (or even mostly) to monitoring of individuals, you do not have a real grasp of the scope and applicability of DNA sequencing.

There are enormous resources in scientific research that goes toward generating datasets. Sequencing of humans is a significant part of it, but most of that applies to medicinal uses, such as cancer genotyping (which uses sequencing to identify specifically the genotypic characteristics of a particular tumor colony so it can be treated much more effectively than just trying to guess by looking at it "from the outside"). Also, a huge new area in medicine is going to be "personalized" medicine. Medicine that's actually tailored to the specific genetic traits that YOU have, so that the chances of side-effects are reduced and effectiveness is increased.

Then there are the thousands of researchers that need to collect sequence datasets on organisms that have NOTHING to do with humans. A big chunk of this is plant genetics: crop stress tolerance (e.g. make wheat grow more reliably in colder or dryer climates, or resist disease better), natural product optimization (e.g. make canola plants produce 10% more of the kinds of oils you care about, and less of the crap you don't). Another big chunk of this research is basic science: figuring out the specific details of how evolution has progressed, or to identify the core biological processes that make organisms tick. That's core evolutionary biology and biomechanics research.

Then there's the people trying to do constructive genomics: actually build organisms that do specific things. Like modifying yeast to produce some complex bioproduct that requires a network of potentially hundreds of genes. Or creating organisms that filter waste from water. Or building algae variants that run on sunlight and produce oil.

All of these things could desperately use robust, cheap, accessible sequencing platforms. Genetic sequencing is not all about your privacy. It's a platform which has the scope to save scientists and researchers millions, and put that towards more research and better results than towards trying to scrape out a few bases from a tissue sample.

IBM is trying big time to get into the life sciences (that's wrong actually, they actually already HAVE products they market to the life sciences, like systems for large-scale data processing). It is worth billions to them, and they want to tap it.

-Laxitive

Comment Re:Two atoms? (Score 1) 97

I suspect an oil rig, a refinery, a transport truck, and a highway system to deliver the oil, and an oil distribution infrastructure were all part of your car motor too. Because without those it's just a hunk of twisted metal.

-Laxitive

Comment Language is fluid, let it flow (Score 4, Interesting) 431

I was happy to read this article. It reflects what has slowly become my perspective on online use of language.

Speaking as an immigrant who originally struggled with the English language for the first few years I spent in North America, I love English. I love how some parts make no sense, and how it's infused with slang from cultural experiences gathered from far and wide. Formal english is completely different from slang english, pigdin english, or online english... but I don't see the latter examples as _inferior_, simply different... wonderfully different.

People often confuse the notion of "writing English in a way that I can relate to" with "writing good English". This is not so. Language is most exciting when it is adulterated, compromised, and infused with the particulars of its speakers. I spent 3 years of adolescence in Louisiana, back in the 90s. While others were scoffing at the notion of ebonics, I was lapping up inner city slang: that beautiful, musical, profane prose. While others bemoan the so-called regression identified with online linguistic idioms, the 4-chanisms, and earlier the Jeff-K-isms, the flippant irreverence which with modern youth take ownership of their speech, I celebrate it.

Who wants to read things in the same way they've always written? Not to say that great writers of the past are stale - I still relish my Twain, Irving, Rushdie, and other masters of script - but I don't see the point in taking an adversarial perspective on the evolution of language.... and have no doubt, language IS evolving online. Literature is evolving online. The presentation is changing, the context is changing, the composition is changing, the references are changing... it's fucking exciting to watch.

-Laxitive

Comment Re:Cloud Computing? Why? (Score 2, Informative) 154

Really? I see traffic rising on my site. I have 6 servers up and running. I need 6 new servers to come up within the next 10 minutes to service my estimated needs for the next hour.

...half hour passes

Wow, access rate is going up faster than expected. I need 6 more servers.

...half hour passes

Phew. That was over. I just need 6 in total now. Why am I paying for 18? I'd like to take those down, please.

So, tell me.. who has been providing this service for decades?

-Laxitive

Comment Re:Infrastructure will not handle this (Score 2, Insightful) 571

So the smaller cities will become like Delhi or Mumbai, with pollution, dirt, and garbage piling up everywhere.

If you don't think there will be too many people buying this thing as a status symbol, then you don't know Indians. If there's one thing I know about Indians, Northern and Southern, Rich and Poor, High Caste and Low Caste.. it's that status is everything, wealth is status, and cars are wealth. Sure, so is jewelry, and being able to pay for ridiculously overpriced weddings, and a whole bunch of other things.. but the car as a status symbol in India is across the board.

Tata is lying. This is all about making money on top of the Indian desire to keep up with the joneses.

Now, I'm not saying that's a bad desire. Ambition is good. Wanting to have a better life with better conveniences is a good thing. It's what makes India so vibrant and exciting a place. But there is always a cost for this kind of progress, and in a place like India where we really haven't gotten our largest problems sorted out, where we haven't, as a culture, figured out that throwing our garbage onto the streets and shitting in our own water supply is not sustainable in the long term, where we haven't learned that it is unwise spending your entire family fortune on lavish and gaudy weddings and jewellry when it could have been invested in the young couple's livelyhood to far better effect.. I don't think the country as a whole knows what it is getting into.

India may well be careening at breakneck pace towards a brick wall if it doesn't fix the more fundamental issues it faces. And no, cheap cars are not one of those fundamental issues.

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