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Python has always touted itself as a "batteries included" language; its standard library contains lots of useful modules, often more than enough to solve many types of problems quickly. From time to time, though, some have started to rethink that philosophy, to reduce or restructure the standard library, for a variety of reasons. A discussion at the end of November on the python-dev mailing list revived that debate to some extent.

The 4.20.1, 4.19.14, 4.14.92, and 4.9.149 stable kernels have been released; each contains a relatively large set of important fixes.

Security updates have been issued by Arch Linux (elfutils, polkit, and tar), Debian (python-django and ruby-loofah), and Mageia (ansible, avidemux, coreutils, discount, nettle, openafs, opensc, and qtbase5).

Many projects have adopted the "GitHub style" of development over the last few years, though, of course, there are some high-profile exceptions that still use patches and mailing lists. Many projects are leery of putting all of their project metadata into a proprietary service, with limited means of usefully retrieving it should that be necessary, which is why GitLab (which is at least "open core") has been gaining some traction. A recently announced effort looks to kind of bridge the gap; Drew DeVault's sr.ht ("the hacker's forge") combines elements of both styles of development in a "100% free and open source software forge". It looks to be an ambitious project, but it may also suffer from a lack of "social network" effects, which is part of what sustains GitHub as the forge of choice today, it seems.

Version 5.0 of the Bash shell has been released. "The most notable new features are several new shell variables: BASH_ARGV0, EPOCHSECONDS, and EPOCHREALTIME. The `history' builtin can remove ranges of history entries and understands negative arguments as offsets from the end of the history list. There is an option to allow local variables to inherit the value of a variable with the same name at a preceding scope. There is a new shell option that, when enabled, causes the shell to attempt to expand associative array subscripts only once (this is an issue when they are used in arithmetic expressions). The `globasciiranges' shell option is now enabled by default; it can be set to off by default at configuration time."

Security updates have been issued by Debian (libav), Fedora (krb5), Red Hat (source-to-image), and SUSE (gpg2, libgit2, and libsoup).

On the Red Hat community blog, Dave Neary writes about community governance and, in particular, how to choose who gets a vote, who can run, and how to decide a winner when electing a leader or council. He summarizes a number of different options that he has encountered with an eye toward avoiding the deep rat-hole conversations that picking a way to run elections can engender. "Defining the activity metric and minimum bar for what qualifies as participation can become contentious, mainly because where you draw the line will be arbitrary, and will omit people who you want to include, or include people who you want to omit. For example, if you set the bar at the minimum contribution level of one commit to the project, you omit all whose contributions are significant but not code related. The typical fear is ballot stuffing or cohort effects — where large companies will dominate the representative bodies by having a large voting bloc, or where friends of candidates (or people with a certain agenda) will pass the low bar to become voters just to vote for their candidate."

Linus Torvalds released 5.0-rc1 on January 6, closing the merge window for this development cycle and confirming that the next release will indeed be called "5.0". At that point, 10,843 non-merge change sets had been pulled into the mainline, about 2,100 since last week's summary was written. Those 2,100 patches included a number of significant changes, though, including some new system-call semantics that may yet prove to create problems for existing user-space code.

Security updates have been issued by CentOS (keepalived), Debian (python-django), Fedora (tcpreplay), Mageia (apache-commons-compress, aubio, dcraw, freerdp, imagemagick, ldb, talloc, samba, libao, libextractor, libgxps, libpgf, openjpeg2, pdns, pdns-recursor, php-phpmailer, plexus-archiver, units, wget, and xmlrpc), Oracle (keepalived and kernel), and SUSE (polkit and xen).

Linus has released the 5.0-rc1 kernel prepatch and closed the merge window for this development cycle. "The numbering change is not indicative of anything special. If you want to have an official reason, it's that I ran out of fingers and toes to count on, so 4.21 became 5.0."

One of the useful features added during the 4.20 development cycle was the availability of pressure-stall information, which provides visibility into how resource-constrained the system is. Interest in using this information has spread beyond the data-center environment where it was first implemented, but it turns out that there some shortcomings in the current interface that affect other use cases. Suren Baghdasaryan has posted a patch set aimed at making pressure-stall information more useful for the Android use case — and, most likely, for many other use cases as well.

Security updates have been issued by Fedora (wget), Oracle (kernel), Red Hat (keepalived), Scientific Linux (keepalived), and SUSE (GraphicsMagick and mailman).

The fs-verity mechanism, created to protect files on Android devices from hostile modification by attackers, seemed to be on track for inclusion into the mainline kernel during the current merge window when the patch set was posted at the beginning of November. Indeed, it wasn't until mid-December that some other developers started to raise objections. The resulting conversation has revealed a deep difference of opinion regarding what makes a good filesystem-related API and may have implications for how similar features are implemented in the future.

Security updates have been issued by Debian (jasper, libdatetime-timezone-perl, qtbase-opensource-src, thunderbird, and tzdata), Red Hat (rh-perl524-perl), and SUSE (libraw, polkit, and xen).

There are currently a number of sites bouncing emails from LWN.net due to an alleged listing in the dnsbl.njabl.org blacklist. The only problem is that this blacklist has been offline since 2013. That domain has been taken over by somebody else; checking web content at that address is not recommended as it is, to put it lightly, non-technical. If you are not getting expected email from LWN, you might want to look into whether your local setup is still trying to use that old, discontinued blacklist.

Antonio Cuni writes about recent work to support running Python code with low latency requirements under PyPy. "As we said, the total cost of memory management is less on PyPy than on CPython, and it's one of the reasons why PyPy is so fast. However, one big disadvantage is that while on CPython the cost of memory management is spread all over the execution of the program, on PyPy it is concentrated into GC runs, causing observable pauses which interrupt the execution of the user program. To avoid excessively long pauses, the PyPy GC has been using an incremental strategy since 2013. The GC runs as a series of 'steps', letting the user program to progress between each step."

The LWN.net Weekly Edition for January 3, 2019 is available.

The January 3 LWN.net Weekly Edition will be our first for 2019, marking our return after an all-too-short holiday period. Years ago, we made the ill-considered decision to post some predictions at the beginning of the year and, like many mistakes, that decision has persisted and become an annual tradition. We fully expect 2019 to be an event-filled year, with both ups and downs; read on for some wild guesses as to what some of those events may look like.

The Internet Archive (IA) has been around for over 20 years now; many will know it for its Wayback Machine, which is an archive of old versions of web pages, but IA is much more than just that. Tracey Jaquith said that she and her IA colleague David Van Duzer would relate a "love/hate, long adventure story—mostly love" about the migration of parts of IA to Kubernetes. It is an ongoing process, but they learned a lot along the way, so they wanted to share some of that with attendees of KubeCon + CloudNativeCon North America 2018.

The linux-kernel mailing list carries the sad news that Shaohua Li, a talented contributor to much of the core kernel and the maintainer of the MD RAID subsystem, passed away over the holidays. Thank you for your work, Shaohua, you will certainly be missed.