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When OpenAI made its chatbot ChatGPT available to the publicin November 2022, it immediately became a hit. However, despite thecompany's name, the underlying algorithm isn't open. Furthermore, ChatGPTusers require a connection to OpenAI's cloud service and face usagerestrictions. In the meantime, several open-source or freely availablealternatives have emerged, with some even able to run on consumer hardware. Although theycan't match ChatGPT's performance yet, rapid advancements are occurring inthis field, to the extent that some people at the companies developing theseartificial intelligence (AI) models have begun to worry.

Version2.39 of the util-linux tool collection has been released. The mostsignificant change, perhaps, is support for the new filesystem-mounting API, which enables anumber of new features, including ID-mappedmounts.

There are some filesystems that use the Filesystemin Userspace (FUSE) framework but only to provide a different view ofan underlying filesystem, such as different filemetadata, a changed directory hierarchy, or other changes of that sort.The read-only filteredfilesystem, which simply filters the view of which filesare available, is one example; the file data could come directly from theunderlying filesystem, but currently needs to traverse the FUSE user-space serverprocess. Finding a way to bypass the server, so that the file I/O operations godirectly from the application to the underlying filesystem would be beneficial. Ina filesystem session at the 2023 Linux Storage,Filesystem, Memory-Management and BPF Summit, Miklos Szeredi wanted to exploredifferent options for adding such a mechanism, which was referred to asa "FUSE passthrough"—though "bypass" might be a better alternative.

The conversion of the kernel's memory-management subsystem over to folios was never going to be done in a day.At a plenary session at the start of the second day of the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Matthew Wilcox discussed the currentstate and future direction of this work. Quite a lot of progress has beenmade — and a lot of work remains to be done.

A new development in the NVMe world was the subject of a combined storageand filesystem session led by Stephen Bates at the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit. Computational storage namespaceswill allow NVMe devices to offer various types of computation—anything fromsimple compression through complex queries and data manipulations—to beperformed on the data stored on the device.

The use of huge pages can make memory management more efficient in a numberof ways, but it can also impose costs in the form of internal fragmentation andI/O amplification. At the 2023 LinuxStorage, Filesystem, Memory-Management and BPF Summit, James Houghtonran a session on a scheme to get the best of both worlds: using huge pageswhile maintaining base-page mappings within them.

The6.3.3,6.2.16,6.1.29,5.15.112,5.10.180,5.4.243,4.19.283, and4.14.315stable kernels have all been released; each contains another set ofimportant fixes. Note that 6.2.16 will be the final update for the 6.2kernel.

Security updates have been issued by Debian (netatalk), Mageia (connman, firefox/nss/rootcerts, freeimage, golang, indent, kernel, python-django, python-pillow, and thunderbird), Red Hat (apr-util, firefox, java-1.8.0-ibm, libreswan, and thunderbird), SUSE (conmon, curl, java-11-openjdk, and libheif), and Ubuntu (libwebp, linux, linux-aws, linux-aws-5.15, linux-azure, linux-azure-5.15, linux-azure-fde, linux-azure-fde-5.15, linux-hwe-5.15, linux-ibm, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-oracle, linux, linux-aws, linux-aws-hwe, linux-kvm, linux, linux-aws, linux-azure, linux-azure-5.19, linux-kvm, linux-lowlatency, linux-raspi, node-eventsource, and openjdk-8, openjdk-lts, openjdk-17, openjdk-20).

In a plenary session on the first day of the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Stephen Bates led a discussion about peer-to-peer DMA (P2PDMA). The idea is toremove the host system's participation in a transfer of data from onePCIe-connected device to another. The feature was originally aimed at NVMeSSDs so that data could simply be copied directly to and from the storagedevice without needing to move it to system memory and then fromthere to somewhere else.

DAMON is a framework that allows user spaceto influence and control the kernel's memory-management operations. Itfirst entered the kernel with the 5.15 release, and has been gainingcapabilities ever since. At the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, DAMON author Seongjae Park providedan overview of the current status of DAMON development and where it can beexpected to go in the near future.

Security updates have been issued by Debian (epiphany-browser, python-ipaddress, and sqlparse), Fedora (python-django3 and qemu), Red Hat (apr-util, autotrace, bind, bind9.16, container-tools:4.0, container-tools:rhel8, ctags, curl, device-mapper-multipath, dhcp, edk2, emacs, freeradius:3.0, freerdp, frr, gcc-toolset-12-binutils, git, git-lfs, go-toolset:rhel8, grafana, grafana-pcp, gssntlmssp, Image Builder, kernel, kernel-rt, libarchive, libreswan, libtar, libtiff, mingw-expat, mysql:8.0, net-snmp, pcs, php:7.4, poppler, postgresql-jdbc, python-mako, python27:2.7, python38:3.8 and python38-devel:3.8, python39:3.9 and python39-devel:3.9, samba, sysstat, tigervnc, unbound, virt:rhel and virt-devel:rhel, wayland, webkit2gtk3, xorg-x11-server, and xorg-x11-server-Xwayland), SUSE (dmidecode, postgresql13, prometheus-sap_host_exporter, python-cryptography, rekor, and thunderbird), and Ubuntu (firefox, matrix-synapse, and mysql-8.0).

In a remotely presented, memory-management-track session at the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Frank van der Linden pointed out thatthe line dividing resources controlled by the kernel from those managed byuser space has moved back and forth over the years. He is currentlyinterested in making it possible for user space to take more control overthe management of memory resources. A proposal was discussed in generalterms, but it will require some real scrutiny on its way toward themainline, if it ever gets there.

Sourceware.org, which has long played host to many important projects, hasannounced that it has become a member project of the Software FreedomConservancy — a move that has been in theworks for some time.

Overcommitting memory is a longstanding tradition in the Linux world(and beyond); it is rare that an application uses all of the memoryallocated to it, so overcommitting can help to improve overall memoryutilization. In situations where memory has been overcommitted, though, itmay be necessary to respond quickly to ensure that applications have thememory they actually need, even when those needs change. At the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, T.J. Alumbaugh (in the room) andYuanchu Xie (remotely)presented a new mechanism intended to help hosts provide containerizedguests with the memory resources they need.

Virtual-machine hosting can be a fickle business; once a virtual machinehas been placed on a physical host, there may arise a desire to move it toa different host. The problem with migrating virtual machines, though, isthat there is a period during which the machine is not running; that can bedisruptive even if it is brief. At the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Dragan Stancevic, presentingremotely, showed how CXLshared memory can be used to migrate virtual machines with no offline time.

Security updates have been issued by Debian (golang-websocket, kernel, postgresql-11, and thunderbird), Fedora (firefox, kernel, libreswan, libssh, tcpreplay, and thunderbird), SUSE (dcmtk, gradle, libraw, postgresql12, postgresql13, postgresql14, and postgresql15), and Ubuntu (firefox, nova, and thunderbird).

The second 6.4 kernel prepatch is out fortesting. "This being rc2, it's been a fairly calm week as people areonly starting to find any issues from the merge window, but it all looksfine."

The Linux CPU scheduler will let realtime tasks hog the CPU to theexclusion of everything else — except when it doesn't. At the 2023 OpenSource Summit North America, Joel Fernandes covered the problems withthe kernel's realtime throttling mechanism and a couple of potentialsolutions. As a bonus, since the room was unscheduled for the followingslot, attendees were treated to a spontaneous session onadaptive spinning in user space run by André Almeida.

Memory tiering is the practice of dividing physical memory into separatelevels according to its performance characteristics, then allocating thatmemory in a (hopefully) optimal manner for the workload the system isrunning. The subject came up repeatedly during the 2023 Linux Storage, Filesystem,Memory-Management and BPF Summit. One session, led by David Rientjes,focused directly on tiering and how it might be better supported by theLinux kernel.

Kyungsan Kim began his talk at the 2023Linux Storage, Filesystem, Memory-Management and BPF Summit with aclaim that the Compute Express Link (CXL) technology is leading tofundamental changes in computer architecture. The kernel will have torespond with changes of its own, including in its memory-management layer.Drawing on some experience gained at Samsung, Kim had a few suggestions onthe form those changes should take — suggestions that ran into somedisagreement from other memory-management developers.

In part one of the tale, Brandt Bucherlooked specifically at the CPython optimizations that went intoPython 3.11 as part of the Faster CPython project. More of that workwill be appearing in future Python versions, but on day two of PyCon 2023 in Salt Lake City, Utah,Mark Shannon provided an overall picture of CPython optimizations,including efforts made over the last decade or more, with an eye toward theother areas that have been optimized, such as the memory layout for theinternal C data structures of the interpreter. He also described someadditional optimization techniques that will be used in Python 3.12and beyond.

Security updates have been issued by Debian (postgresql-13 and webkit2gtk), Fedora (git), SUSE (helm and skopeo), and Ubuntu (cinder, nova, python-glance-store, and python-os-brick).

Mike Rapoport has put a considerable amount of effort into solving theproblem of direct-map fragmentation over the years; this has resulted inproposals like __GFP_UNMAPPED anda session at the 2022 Linux Storage,Filesystem, Memory-Management, and BPF Summit. Rapoport returned at the 2023 Summit to revisit this issue, but hestarted with a somewhat surprising spoiler.

Greg Kroah-Hartman has announced the release of the 6.3.2, 6.2.15,6.1.28, and 5.15.111 stable kernels. These all containimportant fixes throughout the kernel tree, as usual.

Storage technology may seem like a slow-moving area, but there is, instead,a lot of development activity happening there. An early session at the2023 Linux Storage, Filesystem,Memory-management and BPF Summit, led by Martin Petersen and Vincent Haché, updated the assembled group onthe latest changes to the storage landscape, with an emphasis on theCompute Express Link (CXL) 3.0 specification.

Security updates have been issued by Debian (firefox-esr and nvidia-graphics-drivers-legacy-390xx), Fedora (firefox, java-11-openjdk, LibRaw, moodle, python-django3, and vtk), Slackware (mozilla), SUSE (buildah, cloud-init, container-suseconnect, firefox, golang-github-prometheus-prometheus, kernel, and ntp), and Ubuntu (heat, linux-azure-fde-5.15, linux-raspi, linux-oem-5.17, linux-oem-6.0, linux-raspi, linux-raspi-5.4, linux-raspi2, neutron, openvswitch, and sqlparse).

Michael Catanzaro has posted anupdate on the state of the GNOME core apps collection and the processused to make changes to it.

The LWN.net Weekly Edition for May 11, 2023 is available.

The MicroPython programming language implements a sizable subset of Python that can run on microcontrollers, thus bringing Python's easy-to-learn syntax, readability, and versatility to the embedded world. With its recent 1.20 release, MicroPython introduces a new package manager, reduces its code size, and adds supportfor many new boards, including the Raspberry PiPico W. The project has come a long way since its inception ten years ago, making it an easy-to-use tool for developing software forresource-constrained environments.

Version1.9 of the Julia language has been released. Notable changes includeimproved caching of native code, faster load times via a "packageextensions" mechanism, better memory-usage introspection, and more.

Security updates have been issued by Debian (emacs), Fedora (chromium, community-mysql, and LibRaw), Red Hat (nodejs nodejs-nodemon, nodejs:18, and webkit2gtk3), Slackware (mozilla), SUSE (amazon-ssm-agent, conmon, distribution, docker-distribution, google-cloud-sap-agent, ignition, kernel, ntp, prometheus-ha_cluster_exporter, protobuf-c, python-cryptography, runc, and shim), and Ubuntu (ceph, freetype, and node-css-what).

The Thunderbird email-client project has put out areport describing its financial situation in 2022.

Two members of the FasterCPython team, which was put together at Microsoft at the behest of Guidovan Rossum to work on major performance improvements for CPython, cameto PyCon 2023 to report on what theteam has been working on—and its plans for the future. PEP 659 ("SpecializingAdaptive Interpreter") describes the foundation of the current work, someof whichhas already been released as part of Python 3.11. Brandt Bucher, whogave a popular talk on structural pattern matchingat last year's PyCon, was up first, with a talk on what "adaptive" and"specializing" mean in the context of Python, which we cover here in partone. Mark Shannon, whose proposed planfor performance improvements in 2020 was a major impetus for this work,presented on the past, present, and future of the Python performanceenhancements, which will be covered in part two.

Version113.0 of the Firefox browser is out. Changes include improvedpicture-in-picture support, blocking of third-party cookies in privatewindows, some accessibility improvements, and more. "A 13-year-oldfeature request was fulfilled and Firefox now supports files beingdrag-and-dropped directly from Microsoft Outlook".

Security updates have been issued by Fedora (java-11-openjdk-portable and rubygem-redcarpet), Red Hat (autotrace, bind, buildah, butane, conmon, containernetworking-plugins, curl, device-mapper-multipath, dhcp, edk2, emacs, fence-agents, freeradius, freerdp, frr, fwupd, gdk-pixbuf2, git, git-lfs, golang-github-cpuguy83-md2man, grafana, grafana-pcp, gstreamer1-plugins-good, Image Builder, jackson, kernel, kernel-rt, krb5, libarchive, libguestfs-winsupport, libreswan, libtiff, libtpms, lua, mysql, net-snmp, openssh, openssl, pcs, php:8.1, pki-core, podman, poppler, postgresql-jdbc, python-mako, qemu-kvm, samba, skopeo, sysstat, tigervnc, toolbox, unbound, webkit2gtk3, wireshark, xorg-x11-server, and xorg-x11-server-Xwayland), SUSE (cfengine, cfengine-masterfiles, go1.19, go1.20, libfastjson, python-cryptography, and python-ujson), and Ubuntu (mysql-5.7).

Linus Torvalds released 6.4-rc1 and closed themerge window on May 7. By that time, 13,044 non-mergechangesets had found their way into the mainline repository for the 6.4release. A little over 5,000 of those changesets came in after our summary of the first half of the mergewindow was written. Those changes brought a long list of new featuresand capabilities to the kernel.

Security updates have been issued by Fedora (rust-cargo-c, rust-coreos-installer, rust-fedora-update-feedback, rust-git-delta, rust-gst-plugin-reqwest, rust-pore, rust-rpm-sequoia, rust-sequoia-octopus-librnp, rust-sequoia-policy-config, rust-sequoia-sq, rust-sevctl, rust-tealdeer, and rust-ybaas), Mageia (avahi, git, imagemagick, libfastjson, libxml2, parcellite, and virtualbox), SUSE (containerd, dnsmasq, ffmpeg, git, indent, installation-images, java-17-openjdk, maven and recommended update for antlr3, minlog, sbt, xmvn, ncurses, netty, netty-tcnative, openssl-1_0_0, python-Django1, redis, shim, terraform-provider-helm, and zstd), and Ubuntu (erlang, mysql-5.7, mysql-8.0, ruby2.3, ruby2.5, ruby2.7, and webkit2gtk).

Linus has released 6.4-rc1 and closed themerge window for this development cycle.

Version4.2 of the Yocto Project distribution builder has been released. Itfeatures improved Rust support, a number of BitBake enhancements, lots ofupdated software, and numerous security fixes.

Security updates have been issued by Debian (chromium, evolution, and odoo), Fedora (java-11-openjdk), Oracle (samba), Red Hat (libreswan and samba), Slackware (libssh), SUSE (amazon-ssm-agent, apache2-mod_auth_openidc, cmark, containerd, editorconfig-core-c, ffmpeg, go1.20, harfbuzz, helm, java-11-openjdk, java-1_8_0-ibm, liblouis, podman, and vim), and Ubuntu (linux-aws, linux-aws-hwe, linux-intel-iotg, and linux-oem-6.1).

The SemiAnalysis site has what is said to be aleaked Google document on the state of open-source AI development.Open source, it concludes, is winning.

The 2018 Linux Storage, Filesystem, and Memory-Management (LSFMM)conference included a session onget_user_pages(), an internal kernel interface that can, insome situations, be used in ways that will lead to data corruption orkernel crashes. As the 2023 LSFMM+BPF eventapproaches, this problem remains unsolved and is still the topic of ongoingdiscussion. This patchseries from Lorenzo Stoakes, which is another attempt at a partialsolution, is the latest focus point.

The Red Hat Developer site has anoverview of some of the new C-language features supported by theGCC 13 release.

Security updates have been issued by Fedora (python-sentry-sdk) and Ubuntu (python-django and ruby2.3, ruby2.5, ruby2.7).

The LWN.net Weekly Edition for May 4, 2023 is available.

The Python packaging picture is generally a bit murky; there are lots ofdifferent stakeholders, with disparate wishes and needs, which all adds upto a fairly large set of multi-faceted problems. Back in the first threemonths of the year, we looked at variousdiscussions around packaging, some of which are still ongoing.A packagingsummit was held at PyCon 2023 to bring some of the participants of those discussions together in one room. One of its sessionswas on addinga namespaces feature to the Python PackageIndex (PyPI). It provides a look into some of thedifficulties that can arise, especially when trying to accommodate a long legacy of existingpractices, which is often a millstone around the neck of those trying tomake packaging improvements.

Security updates have been issued by Debian (avahi, kernel, linux-5.10, nodejs, webkit2gtk, and wpewebkit), Gentoo (chromium, google-chrome, microsoft-edge, dbus, dbus-broker, dhcp, firefox, firejail-lts, libapreq2, libsdl, libsdl2, lua, proftpd, python, PyPy3, sudo, syslog-ng, systemd, tor, uptimed, vim, and xfce4-settings), Oracle (emacs and libwebp), Red Hat (libwebp), Scientific Linux (libwebp), and SUSE (ceph, ffmpeg-4, git, pdns-recursor, and shim).

Version 3.21.0 of the Valgrindcode-analysis tool is out. Changes include better integration with the GDB debugger, better checks for non-portablerealloc() calls, and a number of other improvements.

The Guix project ("a transactionalpackage manager and an advanced distribution of the GNU system") has announceda milestone toward its goal of bootstrapping an entire distribution fromsource:

Security updates have been issued by Debian (libdatetime-timezone-perl and tzdata), Fedora (chromium), Red Hat (emacs and libwebp), Slackware (netatalk), and Ubuntu (php7.0).