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Bitcoin mining power usage estimates: 1-4 GW (anonymous experts quoted by Washington Post; Dec 2017), 3.3 GW (Power Compare, a consultancy; Nov 2017), 0.5 GW (some random blogger who shows his working; Mar 2017). I'm going to trust the last of these to be most reliable, and add a factor of two for a year's worth of growth, and guess 1 GW, acknowledging that there's a big error bar here.

Taking a major gold-mining company (Newmont), their energy usage is 40-50m GJ = 1.4 GW. This is about half diesel fuel, and a quarter from the grid. They produce ~5m oz/yr of gold, out of a total global production of 4000 t/yr = 140m oz/yr (some well-referenced table on wikipedia; 2013). Assuming this company is typical, this implies total energy usage for gold mining of 40 GW; the figure for 2018 might be ~2 times higher, judging by the growth trend.

Finally, total global power consumption is ~18,000 GW (an IEA report linked from wikipedia; 2015). So bitcoin mining is ~0.01% of total power usage, and gold mining is ~0.2% of total power usage.

Conclusions: (1) bitcoin mining uses much less (~40x less) power than gold mining; (2) the title of TFA is utter bullshit.

Oh god, the NTFS code is a purple opium-fueled Victorian horror novel that uses global recursive locks and SEH for flow control. Let's write ReFs instead. (And hey, let's start by copying and pasting the NTFS source code and removing half the features! Then let's add checksums, because checksums are cool, right, and now with checksums we're just as good as ZFS? Right? And who needs quotas anyway?)

The full article.

These junior developers also have a tendency to make improvements to the system by implementing brand-new features instead of improving old ones. Look at recent Microsoft releases: we don't fix old features, but accrete new ones. New features help much more at review time than improvements to old ones.

(That's literally the explanation for PowerShell. Many of us wanted to improve cmd.exe, but couldn't.)

> still works for processing just fine...

So you're calling all of the Bitcoin miners liars. That's really nice of you. Your kind is disgusting. That's also what my asshole boss said when he fired our IT director because he couldn't get our new Gigabyte 7850 cards to work because of a Microsoft policy against allowing us to use the cards without a monitor plugged in. Disallowing use of GPUs without a monitor is a very real thing. We ended-up buying 140 KVM ports in order to be allowed to use our video cards.

Since that Microsoft-created fiasco, we have since discovered a cheaper solution to this Microsoft problem, dummy plugs:

http://blog.zorinaq.com/?e=11

Again, it is disgusting the way you describe so many Bitcoin hobbyists and IT professionals.

I wouldn't be so sure—Microsoft's terrible internal organization and infighting have been discussed at length in the past, and it's quite reasonable to say that this is the exact problem that makes their products what we despise. One tiny example: PowerShell was supposed to be an update for the Command Prompt, but because the group that wrote PowerShell wasn't the group in charge of the core system, it had to be shipped as a separate product. The fiefdom regime essentially makes it difficult or impossible to contribute to projects that aren't your own, creating huge barriers to contributing bugs; everything is its own little cathedral. Here's a more detailed rant on the technical consequences from an anonymous MS employee.

Despite I agree with you pretty much, I have to say something against the idea of Windows being closely coordinated and not hacked together with praying it will work. This is a confession of one of the windows kernel developers. It almost made me cry.

The link's gone from HN, but it's still up here:

http://blog.zorinaq.com/?e=74

I always like to go back to first principles. When Patterson, Gibson, Katz first described RAID, they detailed how it worked, and how you can break the data up over multiple inexpensive disks, how can you stripe data, and how to use parity. In 1987, x86 architectures were a 286 or maybe a 386. So, when they implemented parity for RAID, it had to be done in specialized hardware, because the CPUs are not fast enough. We have all seen how a Windows NT 4 server slowed to a crawl when you turn on the openGL screen saver, or used winmodems. The CPUs in those days were simply slow.

Today, a Phenom II X4 945 can compute RAID6 parity at close to 8GB/s. A throughput of 500 MB/s requires less than 1.5% of CPU time. (see: http://blog.zorinaq.com/?e=10)

Now, of course, there's some overhead, processes swapping, etc. And RAID is more than simply calculating parity. The numbers I have seen do not go above 5% of one core however.

Can specialized chips implement RAID functionality faster than an Intel CPU? Sure, that's obvious. But again - if your server cannot handle a 5% load on one CPU on top of what it is already handling - you are sizing it wrong.

Why would software RAID be better? Because you cannot easily implement new technologies like ZFS in hardware. Well, you could, after all, firmware is just software that's written to a chip instead of the hard drive, and runs whatever processes/algorithms you want it to run, on whatever processors. But when new revisions of ZFS come out, it is not as easy to upgrade.

By the way, this is assuming well implemented software raid. Crappy software raid will give you really crappy performance, obviously.

As an example - Cisco always used low powered CPUs (compared to their competitors) and always marketed their "we have specialized hardware ASICS for switching and routing" because they were too cheap to use real CPUs. And so what happens when you cross the threshold for whatever they designed the ASICs to hold/process? Your performance dives off a cliff. Or what happens when you implement IPSec? Or IPv6? Well, buy more Cisco equipment I guess. Cisco's CEO thanks you: http://etherealmind.com/poster-reassuringly-expensive/

Now go watch this: http://video.google.com/videoplay?docid=-6304964351441328559# at :34'50" they tell you software raid gave them a 20% to 30% increase over hardware raid.

This old dog has learnt to go with the times. You should too.

I give up. I gave you links from multiple independent research groups who show something needs explaining but you keep ignoring them... Read again from Thermacore, the CERN, Piantelli, Focardi, the Italian ENEA (equivalent to the US Dept of Energy). All are linked from http://blog.zorinaq.com/?e=61 You have to read the research papers yourself and then make up your own mind.

http://blog.zorinaq.com/?e=61

This covers 20 years of research of "anomalous heat" coming from nickel-hydrogen cells which is the basis of Rossi's technology. Did you that numerous prominent Italian scientists believe Rossi is onto something? Did you know that a former Greek ambassador to Italy and scientist became involved with Rossi to manufacture the E-Cat via an independent company (Defkalion)? And now this company claims to have reverse engineered Rossi's device, and is on a race to ship something before Rossi?

I have been following very closely the whole story around Rossi's E-Cat device for 3 months, and it is so much more complex and fascinating than what you all think...

You are wrong. The anomalous heat detected in some experiments is statistically significant. Just one example: in a 1998 experiment, Focardi had set up a cell that ran continuously for 278 days and produced an excess power of about 900 megajoule: http://www.lenr-canr.org/acrobat/FocardiSlargeexces.pdf

The problem is that this experiment, and many others, despite providing very interesting results, have been mostly ignored by the scientific community purely because of the stigma associated to Cold Fusion research. This is frustrating!

The submitter is also incorrect when saying that Rossi provided no details about how his reactors work. He explained that (a) he processes the nickel powder to create tubercles and enhance its contact surface with hydrogen, (b) he uses 2 nickel isotopes to enhance the reaction, (c) he splits molecular hydrogen (H2) into atomic hydrogen (H1), (d) he uses high pressure and temperature to initiates the reaction, etc.

I used to think that Rossi's E-Cat was a scam, but after researching deeply the subject, I am now convinced this guy might be onto something, see this post I wrote explaining many Cold Fusion experiments that seem to support Rossi and that have been ignored by the community at large: http://blog.zorinaq.com/?e=61

you can buy a 20 or 24 bay case for around $300-$400 US, e.g. Norco RPC-4020 or RPC-4224. Takes up to a full size EEB 12"x13" motherboard and 20 or 24 3.5" hot-swap SAS/SATA drives. Can take a standard power supply or there are redundant dual power supplies available.

http://www.norcotek.com/item_detail.php?categoryid=1&modelno=RPC-4020
http://www.norcotek.com/item_detail.php?categoryid=1&modelno=RPC-4224

The 24 port version has a nice option to replace the internal fan bracket (which supports 4 x 80mm fans) with a bracket that supports 3 x 120mm fans. Much quieter for a home environment. Dunno if the RPC-4020 has a similar option. You *WILL* want to replace all of the supplied fans with third-party silent fans. http://www.silentpcreview.com/ is a good place to start researching this.

Even if you're only planning to have 10 or less drives right now, the extra bays are useful if/when you need to replace or upgrade existing drives. You won't have to juggle drives in and out of bays just to replace them. or have a drive hanging outside the case for a few hours while the data is copied.

For extra SATA ports, there are several models of LSI 9211 and similar HBA adaptors providing SAS/SATA 6Gpbs, PCI-e 8x slot. RRP is around $350 for 8 port models but you can find them cheaper on ebay, and several manufacturers (e.g. the IBM M1015) have significantly cheaper rebadged models. A SAS card allows you to use either or both SAS and SATA drives, and also allows you to use SAS expanders (to attach more drives to the one card - SATA has something similar called "port multipliers" but it's a crappy substitute only good for destroying your data). Unless you don't have enough PCI-e 8x slots in your m/b, though, you're better off just buying more 8 port cards.

They're just "dumb" HBAs offering only RAID-0, RAID-1, and JBOD....but that's exactly what you want for software raid or btrfs or ZFS so why pay extra for RAID-5 in the card that you're never going to use.

The LSI 1068 based cards are even cheaper, but they only support SAS/SATA 3Gbps. Doesn't matter much for current hard disks, but you'll need a few 6Gbps ports on the motherboard if you want to use SSD drives (e.g. for caching.)

here's a good starting point: http://blog.zorinaq.com/?e=10

see also http://forums.servethehome.com/showthread.php?19-LSI-RAID-Controller-HBA-Equivalency-Mapping

For the file system, I very strongly recommend ZFS On Linux (the native kernel implementation, not the ZFS-Fuse module). http://zfsonlinux.org/ - gives you raid-like features, disk/volume management, compression, de-duping, snapshots, ssd caching and more. all data is checksummed too so it can detect errors (and automatically repair them from redundant info on the RAID1/5-like volumes).

The Ubuntu PPA compiles easily on debian (you only have to change one dependancy from zfs-grub to grub in the debian/control file) - it's about 10 minutes work, and most of that is waiting for the packages to compile.

ZFS will give you software-raid like capabilities - superior equivs to RAID-0, RAID-1, and RAID-5/6 and combinations of them, plus multiple optional hot and cold spares. "superior" because the redundancy is on the file/data level, not at the block level, and each block of each file is checksummed. Plus you can use one or more fast devices like an SSD for automatic read caching of frequently access data (ZFS cache or L2ARC), and for a write-intent log (ZFS ZIL) for buffering random-writes to an SSD before writing them to the main drives. This ZIL eliminates the final advantage that hardware raid cards had

The best guess I've seen so far (admittedly, it was just speculation) was that the difference might be due to variable timing delays introduced by the FPGA-based data acquisition system.

On "why does NetApp sell their PCIe NAND flash card $30k?", here is your answer, Chris Rima: http://blog.zorinaq.com/?e=37

In a 3 words: because NetApp can.

It's not the components or engineering behind the card that cost $30k. NetApp prices it so high because the card boosts the performance of their filers by about the same amount as a ~$50k shelf of SAS disks (click that link and go read NetApp's own marketing documentation). They have got to have price points that make sense to customers.

(I know a fraction of you will think "No way!". Well, arbitrary price markups on enterprise gear do exist. This NetApp Flash Cache is effectively priced $150/GB. How do you think that certain competitors can even sell _enterprise_ flash at well below $10/GB? We are not talking 25 or 50% less, but a whole order of magnitude less expensive!)

Uh, no you couldn't. The rate of bitcoin creation is fixed (it's about 50 BTCs / 10 mins, for now). If you add more computational time the system will adjust and it'd become proportionally harder to generate them, so the global rate would keep stable.

So despite the 100 thousand-fold increase in mining difficulty in the past 15 months, the network continuously self-adjusts itself to issue one block of Bitcoins about every 10 minutes. The difficulty increase is entirely caused by users competing between themselves to acquire these blocks.

http://blog.zorinaq.com/?e=49

Bitcoin's existence is essentially technically insuppressible at this moment: it is fully peer-to-peer, there is no central server or company that can be shut down.

The only risk is social: in other words people could simply lose interest in it. But its network strength (hash rate) has demonstrated a remarkable exponential growth recently. It has doubled every 27 days, continuously, in the last 15 months: http://blog.zorinaq.com/?e=49 This implies, of course, popularity. So I would say it is very improbable for Bitcoin to just disappear tomorrow.

What's new, compared to other past announcements that "GSM has been broken" is that, 3 days ago, the A5/1 Project just wrote the piece of code to perform lookups in the "Berlin rainbow table set". The table set is 2TB and has been computed some time ago and can be obtained from various origins (the project member who wrote the lookup code --Frank Stevenson-- offered the arrangement of swapping preloaded disks for cash at the Schiphol airport). See my blog for some more info about these recent developments.

Disabling javascript is not sufficient. The malicious site could very well redirect to the malicious page after a long period of time, say 10min, with:

<meta http-equiv="refresh" content="600;url=http://example.com/malicious-gmail-login-page" />

Although it is a little less sophisticated, it would work. Personally I have always been using 2 browsers for other reasons (to defend myself against CSRF vulnerabilities) and it turns out that doing so also protects me from 'tabnapping', even though CSRF and tabnapping are 2 completely different attacks. I described my setup here. This is a good example of defense-in-depth: using a security policy that ends up preventing future attacks that were unknown at the time the policy was implemented :-)