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Linux

Will Systemd 245 Bring Major Changes to Linux's Home Directory Management? (techrepublic.com) 345

Camel Pilot (Slashdot reader #78,781) writes: Leannart Poettering is proposing homed to alter the way Linux systems handle user management. All user information will be placed in a cryptographically signed JSON record, such as username, group membership, and password hashes. The venerable /etc/passwd and /etc/shadow will be a thing of the past. One of the claimed advantages will be home directory portability.

"Because the /home directory will no longer depend on the trifecta of systemd, /etc/passwd, and /etc/shadow, users and admins will then be able to easily migrate directories within /home," writes Jack Wallen at TechRepublic. "Imagine being able to move your /home/USER (where USER is your username) directory to a portable flash drive and use it on any system that works with systemd-homed. You could easily transport your /home/USER directory between home and work, or between systems within your company."

What is not clear is that for portability, systems would have to have identical user_id, group names, group_id, etc. And what mechanism is going to provide user authorization to login to a system?

"At the moment, systemd 245 is still in RC2 status," the article notes, adding "The good news, however, is that systemd 245 should be released sometime this year (2020).

"When that happens, prepare to change the way you manage users and their home directories."
Programming

The Growth of Command Line Options, 1979-Present (danluu.com) 83

Dan Luu, writing in a blog post: The sleight of hand that's happening when someone says that we can keep software simple and compatible by making everything handle text is the pretense that text data doesn't have a structure that needs to be parsed4. In some cases, we can just think of everything as a single space separated line, or maybe a table with some row and column separators that we specify (with some behavior that isn't consistent across tools, of course). That adds some hassle when it works, and then there are the cases where serializing data to a flat text format adds considerable complexity since the structure of data means that simple flattening requires significant parsing work to re-ingest the data in a meaningful way. Another reason commands now have more options is that people have added convenience flags for functionality that could have been done by cobbling together a series of commands. These go all the way back to v7 unix, where ls has an option to reverse the sort order (which could have been done by passing the output to tac).

[...] Over time, more convenience options have been added. For example, to pick a command that originally has zero options, mv can move and create a backup (three options; two are different ways to specify a backup, one of which takes an argument and the other of which takes zero explicit arguments and reads an implicit argument from the VERSION_CONTROL environment variable; one option allows overriding the default backup suffix). mv now also has options to never overwrite and to only overwrite if the file is newer. mkdir is another program that used to have no options where, excluding security things for SELinux or SMACK as well as help and version options, the added options are convenience flags: setting the permissions of the new directory and making parent directories if they don't exist. If we look at tail, which originally had one option (-number, telling tail where to start), it's added both formatting and convenience options For formatting, it has -z, which makes the line delimiter null instead of a newline. Some examples of convenience options are -f to print when there are new changes, -s to set the sleep interval between checking for -f changes, --retry to retry if the file isn't accessible.

Linux

Linux is Ready for the End of Time (zdnet.com) 100

January 19, 2038 is for Linux what Y2K was for mainframe and PC computers in 2000, reports ZDNet. It's the day that the value for time "runs out of numbers" and, in the case of 32-bit Unix-based operating systems like Linux and older versions of macOS, "starts counting time with negative numbers..."

"But the fixes are underway to make sure all goes well when that fatal time rolls around." nickwinlund77 shared their report: Linux developers have seen this coming for decades. So, Linux kernel developer Arnd Bergmann and others have been working on a repair. These corrections are now in the forthcoming Linux 5.6 kernel. Bergmann explained, "Linux-5.6, or my backport of the patches to 5.4, should be the first release that can serve as a base for a 32-bit system designed to run beyond year 2038."

There are some caveats:

- All user space must be compiled with a 64-bit time_t, which will be supported in the coming musl-1.2 and glibc-2.32 releases, along with installed kernel headers from Linux-5.6 or higher.

- Applications that use the system call interfaces directly need to be ported to use the time64 syscalls added in Linux-5.1 in place of the existing system calls.

- Applications that use a private copy of kernel uapi header files or their contents may need to update to the Linux-5.6 version.

- A few remaining interfaces cannot be changed to pass a 64-bit time_t in a compatible way, so they must be configured to use CLOCK_MONOTONIC times...

After we fix this, we won't have to worry about 64-bit Linux running out of seconds until 15:30:08 GMT Sunday, December 4, 29,227,702,659. Personally, I'm not going to worry about that one.

Programming

Are There Generational Differences In First Coding Languages and Learning Resources? (hackerrank.com) 168

"Under the age of 39? Odds are that most of your peers learned to code in C.

"Most Baby Boomers and Gen Xers — or, those between the ages of 40 and 74 in 2020 — learned to code in BASIC."

That's just one of the interesting conclusions from HackerRank's third annual "Developer Skills Report," which this year compiled responses from over 116,000 developers (from 162 different countries). Developed for educational use in 1964, BASIC was a popular instructional language in college classrooms. But that began to change in 1972, when Bell Labs invented C, allowing portability of the Unix operating system. Though it wasn't an instant hit, the language rose to popularity in the late 70s and early 80s alongside the growth of Unix. Today, the language is celebrated for its longevity, flexibility, and ease of use — just some of the reasons it's still popular for Gen Zers learning to code today.

Gen Z is more likely than any previous generation to utilize bootcamps. Nearly one in six say they've leveraged bootcamps to learn new skills. On the flip side, they're less likely to learn coding skills from older generations' go-tos, like books and on-the-job training. As Gen Z comes to rely more heavily on non-traditional education sources like bootcamps, they're poised to become a key talent pool.

Jaxenter also summarizes another interesting finding from the survey. "72% of hiring managers reported that bootcamp grads were equally or better equipped for their job." The I-Programmer site even noted the top reasons managers gave the surveyors for why bootcamp grads exceed:
  • Ability to learn new technologies & languages quickly (71%)
  • Strong practical experience (61%)
  • Eager to take on new responsibilities (52%)

And they also summarize another interesting result. "Almost a third of developers at small companies (1-49 employees) haven't obtained a Bachelor's degree -- a proportion that drops to only 9% in companies with 10,000 or more employees."


Security

Serious Flaw That Lurked In Sudo For 9 Years Hands Over Root Privileges (arstechnica.com) 96

An anonymous reader quotes a report from Ars Technica: Sudo, a utility found in dozens of Unix-like operating systems, has received a patch for a potentially serious bug that allows unprivileged users to easily obtain unfettered root privileges on vulnerable systems. The vulnerability, tracked as CVE-2019-18634, is the result of a stack-based buffer-overflow bug found in versions 1.7.1 through 1.8.25p1. It can be triggered only when either an administrator or a downstream OS, such as Linux Mint and Elementary OS, has enabled an option known as pwfeedback. With pwfeedback turned on, the vulnerability can be exploited even by users who aren't listed in sudoers, a file that contains rules that users must follow when using the sudo command.

"Exploiting the bug does not require sudo permissions, merely that pwfeedback be enabled," an advisory published by sudo developers said. "The bug can be reproduced by passing a large input to sudo via a pipe when it prompts for a password." The advisory lists two flaws that lead to the vulnerability. The first: pwfeedback isn't ignored as it should be when reading from something other than a terminal. As a result, the saved version of a line erase character remains at its initialized value of 0. The second contributor is that the code that erases the line of asterisks doesn't properly reset the buffer position if there is an error writing data. Instead, the code resets only the remaining buffer length. As a result, input can write past the end of the buffers. Systems with unidirectional pipe allow an attempt to write to the read end of the pipe to result in a write error. Because the remaining buffer length isn't reset correctly when write errors result from line erasures, the stack buffer can be overflowed.
The report notes the vulnerability was introduced in 2009 and remained active until 2018, with the release of 1.8.26b1. "Systems or software using a vulnerable version should move to version 1.8.31 as soon as practical," reports Ars. "Those who can't update right away can prevent exploits by making sure pwfeedback is disabled."
Databases

'Top Programming Skills' List Shows Employers Want SQL (dice.com) 108

Former Slashdot contributor Nick Kolakowski is now a senior editor at Dice Insights, where he's just published a list of the top programming skills employers were looking for during the last 30 days.
If you're a software developer on the hunt for a new gig (or you're merely curious about what programming skills employers are looking for these days), one thing is clear: employers really, really, really want technologists who know how to build, maintain, and scale everything database- (and data-) related.

We've come to that conclusion after analyzing data about programming skills from Burning Glass, which collects and organizes millions of job postings from across the country.

The biggest takeaway? "When it comes to programming skills, employers are hungriest for SQL." Here's their ranking of the top most in-demand skills:
  1. SQL
  2. Java
  3. "Software development"
  4. "Software engineering"
  5. Python
  6. JavaScript
  7. Linux
  8. Oracle
  9. C#
  10. Git

The list actually includes the top 18 programming skills, but besides languages like C++ and .NET, it also includes more generalized skills like "Agile development," "debugging," and "Unix."

But Nick concludes that "As a developer, if you've mastered database and data-analytics skills, that makes you insanely valuable to a whole range of companies out there."


Bug

This Year's Y2K20 Bug Came Directly From 'A Lazy Fix' to the Y2K Bug (newscientist.com) 160

Slashdot reader The8re still remembers the Y2K bug. Now he shares a New Scientist article explaining how it led directly to this year's Y2020 bug -- which affected more than just parking meters: WWE 2K20, a professional wrestling video game, also stopped working at midnight on 1 January 2020. Within 24 hours, the game's developers, 2K, issued a downloadable fix. Another piece of software, Splunk, which ironically looks for errors in computer systems, was found to be vulnerable to the Y2020 bug in November. The company rolled out a fix to users the same week -- which include 92 of the Fortune 100, the top 100 companies in the US....

The Y2020 bug, which has taken many payment and computer systems offline, is a long-lingering side effect of attempts to fix the Y2K, or millennium bug. Both stem from the way computers store dates. Many older systems express years using two numbers -- 98, for instance, for 1998 -- in an effort to save memory. The Y2K bug was a fear that computers would treat 00 as 1900, rather than 2000. Programmers wanting to avoid the Y2K bug had two broad options: entirely rewrite their code, or adopt a quick fix called "windowing", which would treat all dates from 00 to 20, as from the 2000s, rather than the 1900s. An estimated 80 percent of computers fixed in 1999 used the quicker, cheaper option. "Windowing, even during Y2K, was the worst of all possible solutions because it kicked the problem down the road," says Dylan Mulvin at the London School of Economics....

Another date storage problem also faces us in the year 2038. The issue again stems from Unix's epoch time: the data is stored as a 32-bit integer, which will run out of capacity at 3.14 am on 19 January 2038.

Businesses

'My Business Card Runs Linux' (thirtythreeforty.net) 65

Computer engineer George Hilliard says he has built an electronic business card running Linux. From his blog post: It is a complete, minimal ARM computer running my customized Linux firmware built with Buildroot. It has a USB port in the corner. If you plug it into a computer, it boots in about 6 seconds and shows up over USB as a flash drive and a virtual serial port that you can use to log into the card's shell. The flash drive has a README file, a copy of my resume, and some of my photography. The shell has several games and Unix classics such as fortune and rogue, a small 2048, and a small MicroPython interpreter.

All this is accomplished on a very small 8MB flash chip. The bootloader fits in 256KB, the kernel is 1.6MB, and the whole root filesystem is 2.4MB. So, there's plenty of space for the virtual flash drive. It also includes a writable home directory, on the off chance that anyone creates something they want to keep. This is also saved on the flash chip, which is properly wear leveled with UBI. The whole thing costs under $3. It's cheap enough to give away. If you get one from me, I'm probably trying to impress you.
In a detailed write-up, Hilliard goes on to explain how he came up with the design and assembled all the components. Naturally, there were some problems that arose during the construction that he had to troubleshoot: "first, the USB port wasn't long enough to reliably make contact in many USB ports. Less critically, the flash footprint was wrong, which I worked around by bending the leads under the part by hand..."

Impressively, the total cost of the card (not including his time) was $2.88 -- "cheap enough that I don't feel bad giving it away, as designed!"
Android

New Linux Vulnerability Lets Attackers Hijack VPN Connections (bleepingcomputer.com) 43

An anonymous reader writes: Security researchers found a new vulnerability allowing potential attackers to hijack VPN connections on affected *NIX devices and inject arbitrary data payloads into IPv4 and IPv6 TCP streams. They disclosed the security flaw tracked as CVE-2019-14899 to distros and the Linux kernel security team, as well as to others impacted such as Systemd, Google, Apple, OpenVPN, and WireGuard. The vulnerability is known to impact most Linux distributions and Unix-like operating systems including FreeBSD, OpenBSD, macOS, iOS, and Android. A currently incomplete list of vulnerable operating systems and the init systems they came with is available below, with more to be added once they are tested and found to be affected: Ubuntu 19.10 (systemd), Fedora (systemd), Debian 10.2 (systemd), Arch 2019.05 (systemd), Manjaro 18.1.1 (systemd), Devuan (sysV init), MX Linux 19 (Mepis+antiX), Void Linux (runit), Slackware 14.2 (rc.d), Deepin (rc.d), FreeBSD (rc.d), and OpenBSD (rc.d).

This security flaw "allows a network adjacent attacker to determine if another user is connected to a VPN, the virtual IP address they have been assigned by the VPN server, and whether or not there is an active connection to a given website," according to William J. Tolley, Beau Kujath, and Jedidiah R. Crandall, Breakpointing Bad researchers at University of New Mexico. "Additionally, we are able to determine the exact seq and ack numbers by counting encrypted packets and/or examining their size. This allows us to inject data into the TCP stream and hijack connections," the researchers said.

Intel

Top Linux Developer On Intel Chip Security Problems: 'They're Not Going Away.' (zdnet.com) 87

During his Open Source Summit Europe keynote speech, Greg Kroah-Hartman, the stable Linux kernel maintainer, said Intel CPU's security problems "are going to be with us for a very long time" and are "not going away." He added: "They're all CPU bugs, in some ways they're all the same problem," but each has to be solved in its own way. "MDS, RDDL, Fallout, Zombieland: They're all variants of the same basic problem." ZDNet reports: And they're all potentially deadly for your security: "RIDL and Zombieload, for example, can steal data across applications, virtual machines, even secure enclaves. The last is really funny, because [Intel Software Guard Extensions (SGX)] is what supposed to be secure inside Intel ships" [but, it turns out it's] really porous. You can see right through this thing." To fix each problem as it pops up, you must patch both your Linux kernel and your CPU's BIOS and microcode. This is not a Linux problem; any operating system faces the same problem.

OpenBSD, a BSD Unix devoted to security first and foremost, Kroah-Hartman freely admits was the first to come up with what's currently the best answer for this class of security holes: Turn Intel's simultaneous multithreading (SMT) off and deal with the performance hit. Linux has adopted this method. But it's not enough. You must secure the operating system as each new way to exploit hyper-threading appears. For Linux, that means flushing the CPU buffers every time there's a context switch (e.g. when the CPU stops running one VM and starts another). You can probably guess what the trouble is. Each buffer flush takes a lot of time, and the more VMs, containers, whatever, you're running, the more time you lose.
"The bad part of this is that you now must choose: Performance or security. And that is not a good option," Kroah-Hartman said. He added: "If you are not using a supported Linux distribution kernel or a stable/long term kernel, you have an insecure system."
Unix

Project Trident Ditches BSD For Linux (itsfoss.com) 97

Project Trident is moving from FreeBSD to Void Linux, reports Its FOSS: According to a later post, the move was motivated by long-standing issues with FreeBSD. These issues include "hardware compatibility, communications standards, or package availability continue to limit Project Trident users". According to a conversation on Telegram, FreeBSD has just updated its build of the Telegram client and it was nine releases behind everyone else.

The lead dev of Project Trident, Ken Moore, is also the main developer of the Lumina Desktop. The Lumina Desktop has been on hold for a while because the Project Trident team had to do so much work just to keep their packages updated. (Once they complete the transition to Void Linux, Ken will start working on Lumina again.)

After much searching and testing, the Project Trident team decided to use Void Linux as their new base.

More from the Project Trident site: It's important to reiterate that Project Trident is a distribution of an existing operating system. Project Trident has never been a stand-alone operating system. The goal of Project Trident is enhancing the usability of an operating system as a graphical workstation through all sorts of means: custom installers, automatic setup routines, graphical utilities, and more...

The more we've tested Void Linux, the more impressed we have been. We look forward to working with an operating system that helps Project Trident continue to provide a stable, high-quality graphical desktop experience.

Open Source

Flaw In Sudo Enables Non-Privileged Users To Run Commands As Root (thehackernews.com) 139

exomondo shares a report from The Hacker News: A vulnerability has been discovered in Sudo -- one of the most important, powerful, and commonly used utilities that comes as a core command installed on almost every UNIX and Linux-based operating system. The vulnerability in question is a sudo security policy bypass issue that could allow a malicious user or a program to execute arbitrary commands as root on a targeted Linux system even when the "sudoers configuration" explicitly disallows the root access. Sudo, stands for "superuser do," is a system command that allows a user to run applications or commands with the privileges of a different user without switching environments -- most often, for running commands as the root user.

The vulnerability, tracked as CVE-2019-14287 and discovered by Joe Vennix of Apple Information Security, is more concerning because the sudo utility has been designed to let users use their own login password to execute commands as a different user without requiring their password. What's more interesting is that this flaw can be exploited by an attacker to run commands as root just by specifying the user ID "-1" or "4294967295." That's because the function which converts user id into its username incorrectly treats -1, or its unsigned equivalent 4294967295, as 0, which is always the user ID of root user. The vulnerability affects all Sudo versions prior to the latest released version 1.8.28, which has been released today.

Unix

Bell Labs Plans Big 50th Anniversary Event For Unix (bell-labs.com) 44

Photographer Peter Adams launched a "Faces of Open Source" portrait project in 2014. This week he posted a special announcement on the web site of Bell Labs: Later this month, Bell Labs will celebrate the 50th anniversary of Unix with a special two day "Unix 50" event at their historic Murray Hill headquarters. This event should be one for the history books with many notable Unix and computer pioneers in attendance...!

As I was making those photographs (which will be on display at the event), I gained much insight into Bell Labs and the development of Unix. However, it was some of the more personal stories and anecdotes that brought Bell Labs to life and gave me a feel for the people behind the code. One such time was when Ken Thompson (who is an accomplished pilot) told me how he traveled to Russia after the fall of the Soviet Union in order to fly in a MiG-29 fighter jet... Brian Kernighan told me about how a certain portrait of Peter Weinberger found its way into some very interesting places. These included the concrete foundation of a building on Bell Labs campus, the cover images printed onto Unix CD-ROMs, and most notably, painted on the top of a nearby water tower.

Which brings us to another important piece of Unix mythology that I learned about: the fictitious Bell Labs employee G.R. Emlin (a.k.a. "the gremlin").... A lot of this folklore (including the gremlin) is going to be on display at the Unix 50 event. The archivists at Bell Labs have outdone themselves by pulling together a massive collection of artifacts taken from the labs where Unix was developed for over 30 years. I was able to photograph a few of these artifacts last year, but so much more will be exhibited at this event -- including several items from the personal archives of some attendees.

As if that wasn't enough, the event will also showcase a number of vintage computers and a look into Bell Labs future with a tour of their Future X Labs.

The article includes some more quick stories about the Unix pioneers at Bell Labs (including "the gremlin") and argues that "the decision to freely distribute Unix's source code (to anyone who asked for it) inadvertently set the stage for the free and open source software movements that dominate the technology industry today...

"In hindsight, maybe 1969 should be called the 'summer of code.'"
Unix

Computer Historians Crack Passwords of Unix's Early Pioneers (boingboing.net) 60

JustAnotherOldGuy shares a report from Boing Boing: Early versions of the free/open Unix variant BSD came with password files that included hashed passwords for such Unix luminaries as Dennis Ritchie, Stephen R. Bourne, Eric Schmidt, Brian W. Kernighan and Stuart Feldman. Leah Neukirchen recovered an BSD version 3 source tree and revealed that she was able to crack many of the weak passwords used by the equally weak hashing algorithm from those bygone days.

Dennis MacAlistair Ritchie's was "dmac," Bourne's was "bourne," Schmidt's was "wendy!!!" (his wife's name), Feldman's was "axlotl," and Kernighan's was "/.,/.,." Four more passwords were cracked by Arthur Krewat: Ozalp Babaolu's was "12ucdort," Howard Katseff's was "graduat;," Tom London's was "..pnn521," Bob Fabry's was "561cml.." and Ken Thompson's was "p/q2-q4!" (chess notation for a common opening move). BSD 3 used Descrypt for password hashing, which limited passwords to eight characters, salted with 12 bits of entropy.

Sun Microsystems

When Sun Microsystems' Founders and Former Employees Hold a Reunion (infoworld.com) 36

Last week Infoworld reported on a reunion of more than 1,000 former employees of Sun Microsystems including all four founders of the company -- Andreas Bechtolsheim, Vinod Khosla, Scott McNealy, and Bill Joy -- at just their second reunion since the 2010 Oracle acquisition. Prior to the formal festivities, the company founders met with a small group of press persons. Pondering recent developments in computing, Bill Joy, who is now concentrating on climate change solutions, recalled that Sun tried to do natural language processing, but the hardware was not fast enough. Regarding the emergence of the iPhone, Joy said the advent of mobility and data networks has been transformational for society. He noted that Sun had that kind of vision with Java ME, with Sun trying to do programmable smartphones. "But the hardware was just really nascent at the time," Joy said. Machine learning, though, will be as transformational as the smartphone, he added.

McNealy emphasized Sun's willingness to share technology, such as the Network File System (NFS), which helped to bring about the open source software movement now prevalent today. "We didn't invent open source but we [made it] happen. We were the leader of that parade." Asked if Sun should have moved from Sparc Risc processors and Solaris Unix to Intel processors and Linux, McNealy said he did not want to talk about mistakes he had made as Sun CEO but such a switch was not what Sun should have done....

Among those proudest of Sun's achievements was Sun founder and CEO Scott McNealy, who, taking the stage, had some sharp words for Facebook, which now occupies one of Sun's former Silicon Valley campuses, without mentioning Facebook by name. "I remember some company moved into one of our old headquarters buildings," McNealy said. "And the CEO said, we're going to leave the [Sun Microsystems] logos up because we want everybody in our company to remember what can happen to you if you don't pay attention. This company could do well to do one-one-hundredth of what we did."

GNOME

GNOME 3.34 Released (phoronix.com) 28

Red Hat developer Matthias Clasen has announced the release of GNOME 3.34, bringing many performance improvements and better Wayland support. Phoronix reports: Making GNOME 3.34 particularly exciting is the plethora of optimizations/fixes in tow with this six-month update. Equally exciting are a ton of improvements and additions around the Wayland support to ensure its performance and feature parity to X11. GNOME 3.34 also brings other improvements like sandboxed browsing with Epiphany, GNOME Music enhancements, GNOME Software improvements, and a ton of other refinements throughout GNOME Shell, Mutter, and the many GNOME applications. More details can be found via release announcement and release notes.
Open Source

Celebrating the 28th Anniversary of the Linux Kernel (androidauthority.com) 60

Exactly 28 years ago today, a 21-year-old student named Linus Torvalds made a fateful announcement on the Usenet newsgroup comp.os.minix.

i-Programmer commemorates today's anniversary with some interesting trivia: Back in 1991 the fledgling operating system didn't have a name, according to Joey Sneddon's 27 Interesting Facts about Linux:

Linux very nearly wasn't called Linux! Linus wanted to call his "hobby" project "FreaX" (a combination of "free", "freak" and "Unix"). Thankfully, he was persuaded otherwise by the owner of the server hosting his early code, who happened to prefer the name "Linux" (a combination of "Linus" and "Unix").

One fact I had been unaware of is that the original version of Linux wasn't open source software. It was free but was distributed with a license forbidding commercial use or redistribution. However, for version 0.12, released in 1992, the GPL was adopted making the code freely available.

Android Authority describes the rest of the revolution: Torvalds announced to the internet that he was working on a project he said was "just a hobby, won't be big and professional." Less than one month later, Torvalds released the Linux kernel to the public. The world hasn't been the same since...

To commemorate the nearly 30 years that Linux has been available, we compiled a shortlist of ways Linux has fundamentally changed our lives.

- Linux-based operating systems are the number-one choice for servers around the world... As of 2015, web analytics and market share company W3Cook estimated that as many as 96.4% of all servers ran Linux or one of its derivatives. No matter the exact number, it's safe to say that the kernel nearly powers the entire web...

- In Oct. 2003, a team of developers forked Android from Linux to run on digital cameras. Nearly 16 years later, it's the single most popular operating system in the world, running on more than 2 billion devices. Even Chrome OS, Android TV, and Wear OS are all forked from Linux. Google isn't the only one to do this either. Samsung's own in-house operating system, Tizen, is forked from Linux as well, and it's is even backed by The Linux Foundation.

- Linux has even changed how we study the universe at large. For similar reasons cars and supercomputers use Linux, NASA uses it for most of the computers aboard the International Space Station. Astronauts use these computers to carry out research and perform tasks related to their assignments. But NASA isn't the only galaxy studying organization using Linux. The privately-owned SpaceX also uses Linux for many of its projects. In 2017, SpaceX sent a Linux-powered supercomputer developed by HP to space and, according to an AMA on Reddit, even the Dragon and Falcon 9 run Linux.

"Without it," the article concludes, "there would be no science or social human development, and we would all still be cave-people."
Unix

Some Original Berkeley Unix Pioneers Still Work On The FreeBSD Project (www.tfir.io) 35

Slashdot reader sfcrazy writes: The Linux Foundation hosted the executive director of the FreeBSD Foundation, Deb Goodkin, at the Open Source Summit in San Diego. In this episode of Let's Talk, we sat down with Goodkin to talk about the FreeBSD project and the foundation.
"How did they let you in?" jokes their interviewer.

"They didn't realize that FreeBSD was not a Linux distribution," the executive director replies. "No, but seriously, they've been very welcoming to the FreeBSD community and wanting to include our voice in conversations about open source." FreeBSD is about five and a half million lines of code, versus 35 million for Linux, so "If you want to learn, it's a great way to learn... Someone said they believed that they were a great Linux sys-admin because of knowing FreeBSD."

Founded in 2000 in Boulder, Colorado, the FreeBSD project is a 501(c)(3) -- a public charity -- where the Linux Foundation is a 501(c)(6) -- a trade association. They have 400 committers, and "We're known for excellent documentation," the executive director says in the interview, describing how the community works to welcome new-comers and mentor new contributors. "We actually descended from the original Berkeley Unix. Some of those original people who worked on Berkeley Unix are still involved in the FreeBSD project. They're very approachable. So these young people go to conferences, and here you have Kirk McKusick, who developed UFS and still works on file systems, and he's there, and he's telling stories about back in the day, when he was at Berkeley working with Bill Joy, and he is really interested in helping these new people contribute."

Companies using FreeBSD include Netflix and Apple -- and according to Phoronix, the number of FreeBSD ports has increased to nearly 37,000 packages.
Unix

Can Swap Space Solve System Performance Issues? (utoronto.ca) 201

Earlier this week on the Linux kernel mailing list, Artem S. Tashkinov described a low-memory scenario where "the system will stall hard. You will barely be able to move the mouse pointer. Your disk LED will be flashing incessantly..."

"I'm afraid I have bad news for the people snickering at Linux here," wrote Chris Siebenmann, a sys-admin at the University of Toronto's CS lab. "If you're running without swap space, you can probably get any Unix to behave this way under memory pressure..." In the old days, this usually was not very much of an issue because system RAM was generally large compared to the size of programs and thus the amount of file-backed pages that were likely to be in memory. That's no longer the case today; modern large programs such as Firefox and its shared libraries can have significant amounts of file-backed code and data pages (in addition to their often large use of dynamically allocated memory, ie anonymous pages).
A production engineer (now on Facebook's Web Foundation team) wrote about experiencing similar issues years ago when another company had disabled swapping when they replaced or reinstalled machines -- leading to lots of pages from hosts that had to be dealt with. This week they wrote: I stand by my original position: have some swap. Not a lot. Just a little. Linux boxes just plain act weirdly without it. This is not permission to beat your machine silly in terms of memory allocation, either... If you allocate all of the RAM on the machine, you have screwed the kernel out of buffer cache it sorely needs. Back off.

Put another way, disk I/O that isn't brutally slow costs memory. Network I/O costs memory. All kinds of stuff costs memory. It's not JUST the RSS of your process. Other stuff you do needs space to operate. If you try to fill a 2 GB box with 2 GB of data, something's going to have a bad day! You have to leave room for the actual system to run or it's going to grind to a stop.

News

Linux Journal Ceases Publication (betanews.com) 134

Not too long after Linus Torvalds wrote his own Unix kernel, which he called Linux, in the summer of 1991, a magazine was founded by enthusiasts to focus on the operating system. For nearly three decades Linux Journal has been an authority magazine on all things Linux, but it is now shuttering doors, it said late Wednesday. The announcement comes about two years after the periodical said it would cease to exist, but it was able to find some backing -- from Privacy Internet Access group -- to resume operations later on.

The team said on Wednesday that all staff members had been laid off and the company was left with no operating funds to continue in any capacity. It remains committed to keeping the website afloat for another few weeks.

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