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[UPDATE] Qualcomm, fsck you.

Lately, I posted this: https://www.reddit.com/r/linux/s/hh6TMP6BCS

Here, I discussed about a Wi-Fi firmware/driver/chipset and how it's plaguing The Linux Experience.

I shifted to KDE Neon and continued having these issues. My wlp1s0 was randomly turning off despite trying to make `wifi.powersave=2` or trying to echo the skip_otp option.

Then I noticed the inxi properly.

```
Network:
Device-1: Qualcomm Atheros QCA9377 802.11ac Wireless Network Adapter
vendor: Dell driver: ath10k_pci v: kernel pcie: gen: 1 speed: 2.5 GT/s
lanes: 1 bus-ID: 01:00.0 chip-ID: 168c:0042 class-ID: 0280
IF: wlp1s0 state: up mac: <filter>
IP v4: <filter> type: dynamic noprefixroute scope: global
broadcast: <filter>
IP v6: <filter> type: noprefixroute scope: link
```

Ok... so I have an 802.11ac Wireless adapter. I searched using those keywords, and I found this GLARING GITHUB ISSUE: https://github.com/pop-os/pop/issues/1470

Like, this thing has been plaguing users for 4 YEARS. And if the Wi-Fi doesn't work, then the people who don't wanna delve into firmware, goes back to Windows. I'm not making this up, I have seen in one of the comments of the GitHub Issue itself.

The fault is of Qualcomm's closed-source policy. Even that is fine if the piece of hardware is functional with that closed-source firmware. However, Qualcomm isn't even providing function, but is making everything closed-source. Candela Technologies has released some firmwares of ath10k, but it can only do so much. There still isn't any updated firmware for QCA9377.

Imagine this: because of abandoning closed-source firmware updates, these companies are actually making laptops obsolete, because nobody would have the energy or knowledge to buy a new Wi-Fi chipset. The normal users would just move on from what they might call as their 'obsession' over Linux if they don't get their Wi-Fi working. Worse if that chipset is soldered with the motherboard.

So Qualcomm, fsck you.

https://redd.it/1jzcx7d
@r_linux
I can't close my terminal and I don't know why
https://redd.it/1jzlt8q
@r_linux
I have decided to use Linux on my old laptop... But which distro?

Long story short this laptop is 10 year old and has 4GB of ram until Celeron processor and 500 GB of HDD it's going to be used for to studying again other stuff... which destroy should I use on that is the white I'm not using it daily it's my little sister's laptop and I want to use a graphical UI not any terminal stuff...

https://redd.it/1jzpehr
@r_linux
Lenovo now ship with Fedora
https://redd.it/1jztroz
@r_linux
Linux for a EU smart phone and software eco system?

If the EU is to become independent of the US & China in tech, we need a European smartphone, tablets & laptops, with something else than Android with an Arm CPU. Ideally, a RISC-V CPU designed in/by a European company running some independent form of Linux. But Nokia or Ericsson does not seem to be ready to take up the role they once had.
Is it at all possible and could others do it?

https://redd.it/1jzrv4w
@r_linux
Help! Gnu Grub version 2.12
https://redd.it/1jzzzbc
@r_linux
How useful is Timeshift when moving between distros?

Am I able to use Timeshift if I'm downloading a different distro or can backups only be used in the same distro they were made In (example: Mint>Mint)? Also, what would be difference between the setup options when it asks what files to keep/skip (Keep all>...>exclude all) for Home and Root? Under what circumstances would each option make more or less sense?

https://redd.it/1k0bv8f
@r_linux
Is Linux under the control of the USA gov?

AFAIK, Linux (but also GNU/FSF) is financially supported by the Linux Foundation, an 501(c)(6) non-profit based in the USA and likely obliged by USA laws, present and future.

Can the USA gov impose restrictions, either directly or indirectly, on Linux "exports" or even deny its diffusion completely?

I am not asking for opinions or trying to shake a beehive. I am looking for factual and fact-checkable information.

https://redd.it/1k0ezdi
@r_linux
🔍 From PostgreSQL Replica Lag to Kernel Bug: A Sherlock-Holmes-ing Journey Through Kubernetes, Page Cache, and Cgroups v2

[\(I&GPT\)](https://preview.redd.it/tmkiqilis6ve1.png?width=1280&format=png&auto=webp&s=256b665f3afe4158d541f4b2a240f425e061b347)

What started as a puzzling PostgreSQL replication lag in one of our Kubernetes cluster ended up uncovering... a Linux kernel bug. 🕵️

It began with our Postgres (PG) cluster, running in Kubernetes (K8s) pods/containers with memory limits and managed by the **Patroni** operator, behaving oddly:

* Replicas were lagging or getting dropped.
* Reinitialization of replicas (via pg\_basebackup) was taking **8–12 hours** (!).
* Grafana showed that **Network Bandwidth (BW) and Disk I/O** dropped dramatically — from 100MB/s to <1MB/s — **right after the pod’s memory limit was hit**.

Interestingly, memory usage was mostly in **inactive file page cache**, while **RSS** (Resident Set Size - container's processes allocated MEM) **and WSS** (Working Set Size: RSS + Active Files Page Cache) stayed low. Yet replication lag kept growing.

**So where is the issue..? Postgres? Kubernetes? Infra (Disks, Network, etc)!?**



We ruled out PostgreSQL specifics:

pg\_basebackup was just streaming files from leader → replica (K8s pod → K8s pod), like a fancy rsync.

* This slowdown only happened **if PG data directory size was greater than container memory limit**.
* Removing the memory limit fixed the issue — but that’s not a real-world solution for production.

***So still? What’s going on? Disk issue? Network throttling?***



We got methodic:

* **pg\_dump** from a remote IP > /dev/null → 🟢 Fast (no disk writes, no cache). ***So, no Netw issues?***
* pg\_dump (remote IP) > file → 🔴 Slow when Pod hits MEM Limit. ***Is it Disk???***
* Create and copy GBs of files inside the pod? 🟢 Fast. ***Hm, so no Disk I/O issues?***
* Use **rsync** inside the same container image to copy tons of files from remote IP? 🔴 Slow. ***Hm... So not exactly PG programs issue, but may be PG Docker Image? Olso, it happens when both Disk & Network are involved... strange!***
* Use a completely different image (**wbitt/network-multitool**)? 🔴 Still slow. ***O! No PG Issue!***
* Mount host network (hostNetwork: true) to bypass CNI/Calico? 🔴 Still slow. ***So, no K8s Netw Issue?***
* Launch containers manually with **ctr (*****containerd*****)** and memory limits, no K8s? 🔴 Slow! ***OMG! Is it Container Runtime Issue? What can I do? But, stop - I learned that containers are Linux Kernel cgroups, no? So let's try!***
* Run the same rsync inside a raw **cgroup v2 with memory.max set** via **systemd-run**? 🔴 Slow again! **WHAT!?? (*****Getting crazy here*****)**



But then, trying deep inspect, analyzing & repro it …

👉 On my **dev machine** (Ubuntu 22.04, kernel 6.x): 🟢 All tests ran smooth, no slowdowns.

👉 On Server there was Oracle Linux 9.2 (kernel 5.14.0-284.11.1.el9\_2, RHCK): 🔴 Reproducible every time! So..? Is it Linux Kernel Issue? (***Do U remember that containers are Kernel namespaced and cgrouped processes? ;)***)

So I did what any desperate sysadmin-spy-detective would do: started swapping kernels.

But before of these, I've studied a bit on Oracle Linux vs Kernels Docs ([https://docs.oracle.com/en/operating-systems/oracle-linux/9/boot/oracle\_linux9\_kernel\_version\_matrix.html](https://docs.oracle.com/en/operating-systems/oracle-linux/9/boot/oracle_linux9_kernel_version_matrix.html)), so, let's move on!

🔄 I Switched from RHCK (Red Hat Compatible Kernel) → **UEK (Oracle’s own kernel)** via grubby → 💥 **Issue gone**.

Still needed RHCK for some applications (e.g. **\[Censored\] DB** doesn’t support UEK), so we tried:

* RHCK from **OL 9.4** (5.14.0-427) → FIXED
* RHCK from **OL 9.5** (5.14.0-503.11.1) → FIXED (though some HW compat testing still ongoing)



📝 I haven’t found an official bug report in Oracle’s release notes for this kernel version. But behavior is clear:

OL 9.2 RHCK (5.14.0-284.11.1) = broken :(

OL 9.4/9.5 + RHCK = working!

I may just suppose that the memory of my specific