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Comment: Re:ZFS (Score 1) 209 209

If you want per-application snapshots then you want the application to be in charge of the snapshots - not the file system. The file system does not know when an application is finished making changes to a file. Possibly many files must be changed - the file system does not know so it can not make any assumptions. Applications should be in charge of their own document snapshots using some form of version control. If one wanted they should script it so that a ZFS snapshot was generated - but you are better of using git.

With regards to ZFS, the snapshots are generally done at whatever frequency is defined by the administrator. 5min, 30min, 1day - whatever they decide. The snapshots are accessed from the root ".zfs/snapshots/named_snapshot" directory. There is no piecing together of files - the full file-system, as it was at the point in time it was captured, is available in the directory. The snapshots are immutable - the contents will never change so long as the snapshot exists.

Comment: Re:Type C or mini B (Score 1) 106 106

It is more likely that Apple designed USB-C at the same time they designed the Lightning connector. They opted for the Lightning connector and decided to gift USB-C. It is in Apple's best interest for USB to have a good connector.

Looking at how horrible the USB3 connectors are, it all makes sense. USB 3.1 was announced far to quickly for it to have been planned at the time USB 3.0 was being specified. And there was no design debate - the new connector was basically just announced. Looks like someone delivered a fully developed USB-C connector to the USB standard committee and it was enough of an improvement to warrant a new version.

Comment: Re:20% to 40% ??? No. Just no. (Score 2) 597 597

While you are correct, the article is likely talking about all conversions when powering common DC powered appliances. So 24VDC -> 120VAC -> 5VDC. In this scenario, the 20% to 40% could be realized. It all depends on how crappy the other power supplies are. By minimizing the change in voltage you allow the cheap DCDC converters to work more efficiently.

Comment: Re:Twenty Years Ago in Ventura County (Score 1) 395 395

Bottom line: Encourage people to replace clunkers and keep their vehicle well-maintained.

In Japan, this is exactly what is done. Insurance rates increase once your car is beyond a certain age. You do not see many old cars driving around because they cost more to operate then newer vehicles. At lest this is what my Japanese co-worker had to say.

Comment: Re:Fins - probably not. (Score 1) 216 216

The mass could be moved forward and back without changing the direction of the bullet - so long as the bullet is rotating. If it stops rotating, say by hitting an object, then it would absolutely start to tumble. But I was referring to moving the mass perpendicular to that. Basically a pendulum inside the bullet. This would result in the bullet tumbling right away if not controlled. But if controlled, could be used to direct the bullet - at least in theory.

Comment: Re:Wireless Networking (Score 3, Interesting) 484 484

I was using v2 of the router but that should not make a difference. Apple devices use multicast DNS for device discovery. I found that the router would not bridge mDNS packets between the wired and wireless domains. They would at first but eventually they cut out. This can prevent your iPhone from talking with your AppleTV. From the user's perspective, the iPhone is at fault when in reality it is the network.

There were also problems with multiple routers on the same network. A Netgear suppled service (forgotten which one) would conflict the same service on another router when attached to the same network. Eventually one of the routers would crash. But first DHCP would stop working. Caused all sorts of problems.

The routers are great but somehow Netgear really screwed up the firmware. It is possible the latest versions are fine, but then so is OpenWRT.

Comment: Wireless Networking (Score 5, Interesting) 484 484

In my experience many problems can be attributed to networking. Most wireless routers have crap support for device discovery. I have some WNDR3700 routers are they were constantly requiring reboots. The only solution was to install a basic OpenWRT firmware - then they were great.

So when a device can not connect to another, or freezes when communicating over the network - check your wireless network. Many problems that are realized on portable devices can actually be tracked back to other devices entirely.

Comment: Re:Question about the speedometer in the video (Score 1) 189 189

Would that be a noticeable jolt?

No, jolts are caused by acceleration - either positive or negative. If the train was to cut power and naturally decelerate then it would be noticed due to the significant friction at that speed. But simply leveling off the speed would not induce any noticeable jolts.

For the mandatory car analogy - it would be less noticeable then when you remove your foot from the accelerator pedal when driving at low speed (and accelerating at 0.5 m/s).

A commune is where people join together to share their lack of wealth. -- R. Stallman