Language Selection

English French German Italian Portuguese Spanish

Fedora Project / Red Hat Leftovers

Submitted by Roy Schestowitz on Friday 10th of June 2022 12:41:50 AM Filed under
Red Hat
  • Fedora Community Blog: Community Blog monthly summary: May 2022

    In May, we published 17 posts. The site had 7,126 visits from 4,510 unique viewers. 2,591 visits came from search engines, while 61 came from Fedora Discussion and 58 came from Twitter.

    The most read post last month was Help Us Test Fedora Linux 36 Beta wallpaper with 758 views. The most read post written last month was Nest With Fedora: Call for proposals and sponsors with 116 views.

  • EBS Storage Performance Notes – Instance throughput vs Volume throughput

    This is important because we have to be aware of the Maximum Total Throughput Capacity for a specific volume vs the Maximum Total Instance Throughput.

    Because, if your instance type (or server) is able to produce a throughput of 1250MiB/s (i.e M4.16xl)) and your EBS Maximum Throughput is 500MiB/s (i.e. ST1), not only you will hit a bottleneck trying to write to the specific volumes, but also throttling might occur (i.e. EBS on cloud services).

  • Cockpit Project: Cockpit 271

    Cockpit is the modern Linux admin interface. We release regularly.

  • Three insights you might have missed from KubeCon + CloudNativeCon EU [Ed: "Disclosure: TheCUBE is a paid media partner for the KubeCon + CloudNativeCon Europe event." This is paid-for "media" "coverage" -- a growing and disturbing trend]

    If there has been a slowdown in the rush to build new technologies for the Kubernetes and cloud-native world, there wasn’t any sign of it in Valencia, Spain, during the recent KubeCon + CloudNativeCon Europe event.

    The show was a sellout this year, with more than 7,500 attendees. Perhaps even more significant was that 65% of them attended the gathering for the first time. Attendees included a portion of the Cloud Native Computing Foundation’s 7.1 million cloud-native developers, who gathered to hear the latest on the non-profit’s more than 120 active projects.

  • 3 IT hiring myths about generational differences

    Generational stereotypes aren’t always insulting, but they can be harmful and limit our ability to design and deliver the solutions users want. Many people tend to think of the youngest generation of workers as the most innovative and the oldest as technophobic and resistant to change.

    While that perception may be true of some people in each generation, it is generally not supported by data. Here are three generational myths worth dispelling.

  • Digital transformation: 3 ways it changes companies

    I’ve worked on intelligent automation projects with many organizations worldwide, and there is no doubt: The digital transformation process has a huge impact – not only by bringing about obvious initial change but also by affecting business leaders’ outlook for the future.

    One common result is they want more, expect more, and invest more. Here’s why.

  • Using Multipath TCP to better survive outages and increase bandwidth

    MultiPath TCP (MPTCP) gives you a way to bundle multiple paths between systems to increase bandwidth and resilience from failures. Here we show you how to configure a basic setup so you can try out MPTCP, using two virtual guests. We’ll then look at the details of a real world scenario, measuring bandwidth and latency when single links disappear.

  • systemd-oomd issues on desktop [Ed: Systemd is IBM]
    
During the 22.04 cycle, we enabled systemd-oomd [1] by default on
desktop. Since then, there have been reports of systemd-oomd killing
user applications too frequently (e.g. browsers, IDEs, and gnome-shell
in some cases). In addition to a couple of LPs [2][3], I have heard
these reports by word-of-mouth, and there have been discussions on
internal Mattermost. A common theme in these reports is that e.g.
Chrome is killed "suddenly" without any other observable symptoms of
the system nearing OOM.

For more context, systemd-oomd basically has two methods for deciding
a unit's cgroup is a candidate for OOM kill:

1. When total system memory usage _and_ swap usage both exceed
SwapUsedLimit (90% by default, and on Ubuntu) [4], monitored cgoups
with greater than 5% swap usage become OOM kill candidates, and
cgroups with the highest swap usage are acted on first.

2. When a unit's cgroup memory pressure exceeds MemoryPressureLimit
[5] for at least MemoryPressureDurationSec [6], monitored descendant
cgroups will be acted on starting from the ones with the most reclaim
activity to the least reclaim activity.

In the reports I refer to above, applications are being killed due to
(1). In practice, the SwapUsedLimit might be too easy to reach on
Ubuntu, largely because Ubuntu provides just 1GB of swap. Since we
follow the suggestion of setting ManagedOOMSwap=kill on the root slice
[7], every cgroup is eligible for swap kill. When this condition is
met, user applications like browsers are going to be killed first.

While investigating [2], we patched upstream systemd-oomd to fix how
"used memory" was calculated, and we brought the patch into Jammy.
This may have helped the situation a bit, but it does not appear this
was enough to fix the issue entirely.

Given the current situation, I think we should re-consider how
systemd-oomd is configured on Ubuntu. These are the options that come
to mind:

1. Increase SwapUsedLimit (again, currently at 90%). I think this is
probably the safest change, but it is not clear to me how significant
of an impact this would have.

2. Set ManagedOOMSwap more selectively. Again, we currently follow the
recommendation of setting ManagedOOMSwap=kill on the root slice
(-.slice), so every descendant cgroup is a candidate for swap kill. It
_might_ be effective to say "do not swap kill cgroups descendant of
user's app.slice". The downsides of this approach would be that the
configuration does not scale well (i.e. a lot more configuration
needed to get the proper swap kill "coverage"), and this may just
place the problem onto a different class of processes.

3. Do not enable swap kill at all. This would mean systemd-oomd would
only act when memory pressure limits are reached. Given Ubuntu's swap
configuration, does it make sense for systemd-oomd to act on high swap
usage?

4. Increase swap on Ubuntu. I am adding this for completeness, but I
doubt this is a viable option.

I think that either option (1) or (3) would be the most reasonable --
maybe trying (1) first and falling back to (3) if necessary. If anyone
has an opinion on this, or can think of other options, I would
appreciate the input.

Thanks,

Nick 'enr0n' Rosbrook
»

systemd Kills Apps Too Frequently – Users Aren't Impressed

Submitted by Roy Schestowitz on Friday 10th of June 2022 01:56:16 AM.
  • Ubuntu 22.04 Kills Apps Too Frequently – Users Aren't Impressed - OMG! Ubuntu!

    If you’ve found memory management in Ubuntu a little on the aggressive side since upgrading to 22.04 LTS know this: you are not alone.

    A discussion on the Ubuntu mailing list highlights issues scores of users are experiencing. Out of the blue, with no indication anything is wrong, apps like Firefox, Chrome, and Visual Studio Code just die… Blink out of existence.

    At fault? Ubuntu 22.04 LTS’s introduction of systemd-oomd, a user-space out of memory killer that’s designed to “take corrective action before an OOM occurs in the kernel space’. When it detects that memory pressure is getting a bit too stressed, it intervenes to ensure the system copes, and (most) things stay running.

    But it seems that it’s being triggered too frequently, killing apps even though memory isn’t at a critical impasse.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

More in Tux Machines

digiKam 7.7.0 is released

After three months of active maintenance and another bug triage, the digiKam team is proud to present version 7.7.0 of its open source digital photo manager. See below the list of most important features coming with this release. Read more

Dilution and Misuse of the "Linux" Brand

Samsung, Red Hat to Work on Linux Drivers for Future Tech

The metaverse is expected to uproot system design as we know it, and Samsung is one of many hardware vendors re-imagining data center infrastructure in preparation for a parallel 3D world. Samsung is working on new memory technologies that provide faster bandwidth inside hardware for data to travel between CPUs, storage and other computing resources. The company also announced it was partnering with Red Hat to ensure these technologies have Linux compatibility. Read more

today's howtos

  • How to install go1.19beta on Ubuntu 22.04 – NextGenTips

    In this tutorial, we are going to explore how to install go on Ubuntu 22.04 Golang is an open-source programming language that is easy to learn and use. It is built-in concurrency and has a robust standard library. It is reliable, builds fast, and efficient software that scales fast. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel-type systems enable flexible and modular program constructions. Go compiles quickly to machine code and has the convenience of garbage collection and the power of run-time reflection. In this guide, we are going to learn how to install golang 1.19beta on Ubuntu 22.04. Go 1.19beta1 is not yet released. There is so much work in progress with all the documentation.

  • molecule test: failed to connect to bus in systemd container - openQA bites

    Ansible Molecule is a project to help you test your ansible roles. I’m using molecule for automatically testing the ansible roles of geekoops.

  • How To Install MongoDB on AlmaLinux 9 - idroot

    In this tutorial, we will show you how to install MongoDB on AlmaLinux 9. For those of you who didn’t know, MongoDB is a high-performance, highly scalable document-oriented NoSQL database. Unlike in SQL databases where data is stored in rows and columns inside tables, in MongoDB, data is structured in JSON-like format inside records which are referred to as documents. The open-source attribute of MongoDB as a database software makes it an ideal candidate for almost any database-related project. This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of the MongoDB NoSQL database on AlmaLinux 9. You can follow the same instructions for CentOS and Rocky Linux.

  • An introduction (and how-to) to Plugin Loader for the Steam Deck. - Invidious
  • Self-host a Ghost Blog With Traefik

    Ghost is a very popular open-source content management system. Started as an alternative to WordPress and it went on to become an alternative to Substack by focusing on membership and newsletter. The creators of Ghost offer managed Pro hosting but it may not fit everyone's budget. Alternatively, you can self-host it on your own cloud servers. On Linux handbook, we already have a guide on deploying Ghost with Docker in a reverse proxy setup. Instead of Ngnix reverse proxy, you can also use another software called Traefik with Docker. It is a popular open-source cloud-native application proxy, API Gateway, Edge-router, and more. I use Traefik to secure my websites using an SSL certificate obtained from Let's Encrypt. Once deployed, Traefik can automatically manage your certificates and their renewals. In this tutorial, I'll share the necessary steps for deploying a Ghost blog with Docker and Traefik.

More on Tux Machines: About ● Gallery ● Forum ● Blogs ● Search ● News ● RSS Feed

Part of Bytes Media ● Sister sites below.

TechBytes Techrights button

Powered by Drupal, an open source content management system

Content available under CC-BY-SA CC

© by original authors

Powered by CentOS 6.5 (GNU/Linux), Varnish, and Drupal 6