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Comment Re:UPS power isn't exactly expensive (Score 1) 117

UPS power isn't expensive, just a hundred dollars and ten or twenty pounds of lead acid batteries and special communication cables and automatic shutdown software to make up for the failure of SSD manufacturers to include a gram or two of capacitor protection.

Real hard drives, by the way, are not at risk of losing their entire contents in an unexpected power loss. Most SSDs are. Not to be used if you actually want your data to still be there when you return in the morning.

The reason why is that SSDs require a drive level transaction potentially putting the entire drive contents at risk to complete any write anywhere on the device. Given that most modern operating systems write to disk for various reasons on a nearly continuous basis the contents of your entire device are pretty almost always at risk with most SSDs.

One new entry to a log file, power failure, and there goes 100 GB of other data, lost without recovery. Sorry.

Comment No supercapacitors? (Score 5, Insightful) 117

I think it is more than a little amusing that anyone cares about performance numbers on a drive like this without first asking whether the drive provides any assurance that it won't catastrophically lose all your data, if not be bricked permanently, due to a simple power loss. That seems to be par for the course with the most of the SSDs on the market. Preserving your data? That is an enterprise feature.

Comment Only incidentally similar to su (Score 5, Informative) 747

machinectl shell is only incidentally similar to su. Its primary purpose is to establish an su-like session on a different container or VM. Systemd refers to these as 'machines', hence the name machinectl.


su cannot and does not do that sort of thing. machinectl shell is more like a variant of rsh than a replacement for su.

Comment Re: No, it is the character pronounced as "no" (Score 1) 196

ASCII is the American Standard Code for Information Interchange, a 7 bit encoding system. The most common strictly 8 bit encoding is ISO-8859-1, slightly expanded by Microsoft as Windows-1252, also known as Win-ASCII.

Of course these days, everyone in their right mind should generally be using UTF-8 for transfer and storage. UCS-16 and UTF-16, though widely used internally, are basically a mistake for that kind of thing.

Comment Re:choose what standard to violate (Score 1) 233

> Huh? The POSIX time specification make it trivial to calculate dates using simple arithmetic

True, but the same property also makes the use of POSIX time for precision timing basically suicidal. POSIX time is a convenient and adequate encoding of civil time, as long as you do not need more than one second of accuracy.

If you want to reliably measure or timestamp anything with more than one second of accuracy you should be using a clock derived or offset from a reliable clock instead. The use of POSIX time for precision timekeeping - even use by such rudimentary applications as 'make' - was defective from the beginning. NTP is equally defective as a consequence.

Comment IPv6 is fatally flawed (Score 1) 595

Since the IETF saw that there was gonna be an industry-wide overhaul in any case, it did this complete overhaul, tossing in everything learnt in the years of IPv4, so that another IP transition won't be likely in the next 50 years, if ever.

By this point, even the luminaries at the IETF have realized that the design for IPv6 as a replacement for IPv4 is fatally flawed. How flawed? Flawed enough that there is a high probability that a worldwide transition to IPv6 will never actually happen.

Now sure, there are technical advantages to a clean slate design, but a clean slate design is also unfortunately almost useless as a replacement for IPv4 in the real world. There is no incremental advantage and extraordinarily high costs to adding a separate numbering plan to an existing network, so no cost conscious organization ever does it unless they are forced to, and probably never will.

At this point I would lay odds on an IPv7 eventually being developed that is a revision of IPv6 with the incorporation of the IPv4 address space in a routeable fashion, and which assigns each IPv4 address a network prefix that an entire subnet of devices may eventually be directly addressed behind, in addition to the default.

Why? Because doing anything else would be one of the biggest wastes of resources the world has ever seen.

Any downsides? An IPv7 router would have bigger routing tables than an IPv6 only router, but the routing tables could be used to route IPv4 packets, and as it is not likely IPv4 is going away anytime soon, the same overhead is there one way or another.

A wide scale deployment of IPv7 would require hardware upgrades in some cases, but for most people it could be deployed silently, without them ever needing to know or care. A simple software update would be all that was necessary, and a few years down the road nearly all IPv4 capable devices would handle the expanded address space in a usable fashion without any renumbering or other configuration changes. That would save billions of dollars a year in unnecessary administration costs worldwide.

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