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Comment Roll it yourself but take responsibility (Score 1) 217 217

Super-Micro has 36 and 72 drive racks that aren't horrible human effort wise (you can get 90 drive racks, but I wouldn't recommend it). You COULD get 8TB drives for like 9.5 cent / GB (including the $10k 4U chassi overhead). 4TB drives will be more practical for rebuilds (and performance), but will push you to near 11c / GB. You can go with 1TB or even 1/2TB drives for performance (and faster rebuilds), but now you're up to 35c / GB.

That's roughly 288TB of RAW for say $30k 4U. If you need 1/2 PB, I'd say spec out 1.5PB - thus you're at $175K .. $200k.. But you can grow into it.

Note this is for ARCHIVE, as you're not going to get any real performance out of it.. Not enough CPU to disk ratio.. Not even sure if the MB can saturate a 40Gbps QSFP links and $30k switch. That's kind of why hadoop with cheap 1CPU + 4 direct-attached HDs are so popular.

At that size, I wouldn't recommend just RAID-1ing, LVMing, ext4ing (or btrfsing) then n-way foldering, then nfs mounting... Since you have problems when hosts go down and keeping any of the network from stalling / timing out.

Note, you don't want to 'back-up' this kind of system.. You need point-in-time snapshots.. And MAYBE periodic write-to-tape.. Copying is out of the question, so you just need a file-system that doesn't let you corrupt your data. DEFINITELY data has to replicate across multiple machines - you MUST assume hardware failure.

The problem is going to be partial network down-time, crashes, or stalls, and regularly replacing failed drives.. This kind of network is defined by how well it performs when 1/3 of your disks are in 1-week-long rebuild periods. Some systems (like HDFS) don't care about hardware failure.. There's no rebuild, just a constant sea of scheduled migration-of-data.

If you only ever schedule temporary bursts of 80% capacity (probably even too high), and have a system that only consumes 50% of disk-IO to rebuild, then a 4TB disk would take 12 hours to re-replicate. If you have an intelligent system (EMC, netapp, ddn, hdf, etc), you could get that down to 2 hours per disk (due to cross rebuilding).

I'm a big fan of object-file-systems (generally HTTP based).. That'll work well with the 3-way redundancy. You can typically fake out a POSIX-like file-system with fusefs.. You could even emulate CIFS or NFS. It's not going to be as responsive (high latency). Think S3.

There's also "experimental" posix systems like ceph, gpfs, luster. Very easy to screw up if you don't know what you're doing. And really painful to re-format after you've learn it's not tuned for your use-case.

HDFS will work - but it's mostly for running jobs on the data.

There's also AFS.

If you can afford it, there are commercial systems to do exactly what you want, but you'll need to tripple the cost again. Just don't expect a fault-tolerant multi-host storage solution to be as fast as even a dedicated laptop drive. Remember when testing.. You're not going to be the only one using the system... Benchmarks perform very differently when under disk-recovery or random-scatter-shot load by random elements of the system - including copying-in all that data.

Comment Git for large files (Score 1) 383 383

Git is an excellent system, but is less efficient for large files. This makes certain work-flows difficult to put into a git-repository. i.e. storing compiled binaries, or when having non-trivial test-data-sets. Given the 'cloud', do you forsee a version of git that uses 'web-resources' as SHA-able entities, to mitigate the proliferation of pack-file copies of said large files. Otherwise, do you have any thoughts / strategy for how to deal with large files?

Comment network-operating systems (Score 1) 383 383

Have you ever considered a network-transparent OS-layer? If not why? I once saw QNX and and how the command line made little differentiation of which server you were physically on. (run X on node 3, ps (across all nodes)). You ran commands pretty much on any node of consequence.. I've ALWAYS wanted this capability in Linux... cluster-ssh is about as close as I've ever gotten. These days hadoop/storm/etc give a half-assed approximation.

Comment GPU kernels (Score 4, Interesting) 383 383

Is there any inspiration that a GPU based kernel / scheduler has for you? How might Linux be improved to better take advantage of GPU-type batch execution models. Given that you worked transmeta and JIT compiled host-targetted runtimes. GPUs 1,000-thread schedulers seem like the next great paradigm for the exact type of machines that Linux does best on.

Comment Re: Not quite true (Score 1) 307 307

Whether the term is enforceable or not is debatable and almost certain to be rendered moot. Unlike US Republicans, UK Conservatives do actually believe in the rule of law and honest business practices (sort of). There isn't any party who believes that screwing the consumer is a constitutional right. There will be a bill passed.

A rather more direct question is whether the hotelier was entitled to collect the charge under the credit card agreement. And that is unambiguous, he isn't. A credit card merchant cannot use a charge card to recover a disputed charge. It does not matter what the purported contract term was or if it is enforceable. The credit card agreements are designed to prevent cardholders from dishonest merchants. So the consumer will get their refund and the hotelier will find themselves facing a 30 quid chargeback fee.

The only option for the hotelier to recover would be to take the matter to court. The most he could win is the hundred pounds, if he lost he would likely be out the legal costs which could be a couple of thousand. Small claims courts don't usually award costs but they might well do so in this case. Judges tend to detest bullies.

Comment Re: Ask the credit card for a refund (Score 1) 307 307

Its more than that, without regulation you end up with a lemon-law market.

Lots of times the difference between an honest product and a dishonest one only becomes apparent years later. If the product is safety equipment you only find out if the hard hat works when someone drops the brick on your head.

The libertarian theory that self interest will drive people to make honest products has turned out to be utterly false. In fact it turns out to be quite difficult for a company that intends to do the right thing to do so. I once had to get a guy fired after I found he had goosed his response rates for customer support calls by deliberately setting the phone tree up as a maze.

People do all sorts of idiotic short sighted stuff. This hotelier for example got his pants in a twist over a bad review and now he has probably sunk his business completely.

Rational choice is not an empirical fact of human behavior. It is a modelling assumption that tends to give good results in certain cases. But it does not hold for corporations because the interests of the corporation are not identical to those of the employees. All those banks who go belly up because the traders get big rewards for raking in profits and face no consequences for a loss. I don't gamble with my own money but if you want to give me $100,000 to gamble with I am happy to take it to Vegas, find a roulette wheel and let you take 100% of any losses and 90% of any gains.

Comment Re:Overly broad? (Score 1) 422 422

Water, when consumed in sufficient quantities to kill you, becomes an acute poison. Both water and sugar have LD50 values where they become an acute poison. But, unlike water, sugar is also a chronic poison...prolonged exposure to it causes chronic health problems. That's what we're talking about here and that's why your water example is a false equivalence.

If you want an actual equivalency, try cigarettes or non-lethal levels of ionizing radiation. You'll find your flippant remarks far less amusing when you use something that's poisonous in the same way as sugar.

Comment Re:I Read TFA... (Score 5, Insightful) 107 107

Read the linked TechCrunch article...it's really a great explanation of everything that's going on. One good example was Mountain View working on a commercial development that would bring 42,550 jobs to the city while only creating additional housing for 7000 people. This in a city where already far more people work than live. To Mountain View, it's simple...residents require more services like schools, fire departments and police than do office complexes. But those workers have to live somewhere and cities like Mountain View that are acting selfishly are pushing rents up in nearby cities.

Two of those cities are San Francisco and Oakland. Both cities have a lot of housing when you ignore one minor detail...the current residents that would need to be displaced. But since all those jobs in Mountain View pay way more than the current residents make, developers and landlords are only too happy profiteer off the well-compensated tech workers by pricing the current residents out of the market.

But, as the piece lays out, it's not tech workers that are to blame and, for the most part, not tech companies either. It's mostly local and state government's 30+ years of stupidity that's led to this. Starting with prop 13 in 1978 and the backlash that led to rent control laws, government created an environment where homeowners fight tooth and nail against new housing and rent control drives rent up by distorting the market. The ensuing difference between controlled and uncontrolled rents causes conflict between tenants and landlords who see how much money they're losing each month. So the city adds even more idiotic regulations that ensure a certain amount of housing is sold/rented below market rates, which has income restrictions that just about guarantee that poor people won't be able to afford them...but zero-income children of parents willing to cosign qualify quite easily.

Meanwhile, companies keep growing/starting up and more and more high-paying jobs keep coming to the area. But thanks to all those "I got mine, screw the rest of you" homeowners who keep new developments from being built, those jobs come without the corresponding increase in necessary housing. So what are current landlords to do...every form of meddling is forcing prices through the roof to the point where only highly-paid professionals can afford them? You could either sit by and allow your tenant to pay you a small fraction of what the place is worth (and sometimes rent it out for full price on AirBnB...no rent control there) or you could use some sleazy tactic to evict the long-time tenant and let the boom dollars roll in. Also, notice I didn't say tech professionals...we make up less than a quarter of the well-to-do SF population...there's more finance than tech.

As per usual, the ones most hurt by this are the working poor. The abject poor are doing the same as ever...when you make zero and live off city-provided social programs, rent prices really don't affect you all that much. But the people trying to be productive members of society are basically forced to move away and commute back to the city. And this has some really nasty side effects...like police officers who have no real attachment to the community they serve because they've been priced out of living there.

Protesting the Google bus makes for a great shot on the 11pm news, but is otherwise counter-productive. If we want to fix the issue, we should:
a) Repeal prop 13, rent control, the below-market-rate program and all the other government meddling.
b) Tell homeowners to go fuck themselves and start building new housing as fast as we can.
c) Add significant tax incentives for people who live close to work. This would have the dual effect of being "green" by reducing commutes and making it unattractive to work in cities that do not provide enough housing to support the businesses there.

Alternatively, we could just accept that poor people will need to move and let it happen. It's heartless, but given how bungling government is, it's pretty much inevitable. The unfortunate part is that what's considered poor is almost ridiculous. Someone making $100k/yr will basically never be able to afford to buy a home in SF.

See...SF and Oakland have a lot to do with Silicon Valley :-)

Comment Re:It already found its place. (Score 1) 333 333

I've got two iPads and I think it's misguided to look at it replacing desktop/laptops or phones. The commonality between those two devices is basically limited to activities that I see as having become commoditized...email, web and the like.

But the iPad has partially replaced two of my other devices. I have a 55" flatscreen and PS3 that get significantly less use these days, and it's mostly because of the iPad. I'm not a heavy gamer, so it's notable that I've filled the PS3 void with games that are significantly simpler than what I have on the PS3, but I still find the greater variety of games available on the iPad compelling. For the price of one PS3 game, I can get ~30 iPad games and augment that with many free games. That means I'm almost never bored, despite the lack of depth of each game. And while the iPad might not be as compelling a media viewing device as my 55" screen, I find myself using it more often. It's more convenient, there's no remotes, no switching inputs and streaming is easier. Media companies often bend over backwards to prohibit streaming to devices that can be hooked up to a TV, but they'll make streaming to an iPad work well. When you add in advantages like not disturbing someone who's sleeping and not needing to pause to go to the bathroom I find myself unconsciously gravitating towards streaming on my iPad.

Any discussion of whether the iPad is displacing another consumer electronic device should include TV and gaming consoles long before you include computers or cell phones.

Comment Re:Build refineries in ND (Score 1) 206 206

There is plenty of capacity in St Louis and room to build more.

The cost of the pipeline is much more than the cost of a refinery. The 'surplus capacity' claim is total nonsense. The tar sludge isn't anything like the crude that the existing refineries process. There would have to be major upgrades in any case. And building a two thousand mile pipeline costs a heck of a lot more than any refinery would.

"You're a creature of the night, Michael. Wait'll Mom hears about this." -- from the movie "The Lost Boys"

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