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Comment Re:We already had this sales pitch... (Score 1) 127

There are a few things wrong with your analysis. The first is that disk writes tend to be bursty for desktop users. You write a few hundred MBs (or a few GBs) and then drop down to an average of a few tens or hundreds of KBs per second. Spinning rust can easily keep up with the average write throughput of a typical user, it's the bursts that it has problems with. If you can buffer a few hundred MBs of writes, reorder them to reduce head movement, and then write them out behind the user, then you'll get much better performance. Obviously, this won't help for server workloads where you're I/O limited all of the time, but it will help a lot with desktop / laptop use.

The second is that one of the big bottlenecks for modern filesystems is the wait until data is safely in persistent storage. System RAM doesn't help here, because it goes away with power failure. To ensure consistency, you have to pause writing parts of an update until you've received confirmation that the previous part is written. In a conventional journaled FS, for example, you don't start writing the updates until you've confirmed that the journal has been committed to disk. With NV cache, you can get this confirmation practically instantly. If there's a power failure, then the drive just has to replay the transactions from NVRAM.

Comment Re:Good - burn it down (Score 1) 76

The idea behind the IoT isn't bad. The execution is horrible.

The idea that you can use the internet as a medium to access parts of your home isn't that bad an idea. That the whole shit is done by corporations that only care about their bottom line and offer your gimmicky toys that are security nightmares is the horrible execution thereof.

Comment Re:Denial-of-Service? (Score 4, Insightful) 76

While I generally agree, I cannot second the idea that it should be legal to break into computers that are insufficiently secured. That would make the internet an even worse place than it already is.

What we need is something like the famous FCC part 15 sticker rules. You know the ones, you can find it on pretty much any electronic device:
(1) This device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause undesired operation.

We need something like this for IoT devices.

Comment Re:Online ? Authors never shopped in real life (Score 2) 195

I thought Waitrose delivered everywhere where they had a large store. Don't they deliver in your area?

For what it's worth, I've had under a dozen substitutions in five years of using Ocado (fewer than I got in any six month period with Tesco before that) and things always come with long shelf lives. They also have excellent customer support and will quickly fix anything that they get wrong.

Comment Re:Online ? Authors never shopped in real life (Score 4, Interesting) 195

Unfortunately groceries kind of suck online in the UK.

Seriously? Between the major supermarket chains and Ocado all providing online order / home delivery, none of them works for you? I'll admit, I gave up on Tesco repeatedly sending me things that were one day away from their use-by date, but there's a reasonable amount of competition.

Comment Re:It's not just shocking, it's stupid (Score 1) 195

You actually see this on Amazon, where a number of third-party sellers automatically set their prices by querying the Amazon price or the cheapest third-party price and undercutting it slightly. This sometimes leads to amusing effects where two third-party sellers are offering something for 10% less than the cheapest other seller and forget to set a minimum price.

Comment Re:Okay, but... (Score 2) 143

"Over a pair of superchargers" means that if two Teslas are charging on the same SC circuit then each of them will only get 60kW. A single Tesla can draw up to 120kW (I routinely get around 115kW on SCs when the battery is almost empty) but that does taper off with the increasing battery charge.

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