Resolving commands 'Killed' on GCP f1-micro Compute Engine instances

Resolving commands 'Killed' on GCP f1-micro Compute Engine instances

When I want to perform a quick task, I generally spin up a Google GCP Compute Engine instance as they’re cheap. However, they have limited resources, particularly memory. When refreshing the package repositories, it’s quite easy to encounter an Out-of-Memory (OOM) situation which results in the command - yum or dnf - is ‘killed’. For example:

$ sudo dnf update 
CentOS Stream 8 - AppStream                                                                                                  8.3 MB/s |  18 MB     00:02    
CentOS Stream 8 - BaseOS                                                                                                      13 MB/s |  16 MB     00:01    
CentOS Stream 8 - Extras                                                                                                      69 kB/s |  16 kB     00:00    
Google Compute Engine                                                                                                         20 kB/s | 9.4 kB     00:00    
Google Cloud SDK                                                                                                              24 MB/s |  43 MB     00:01    
Killed

dmesg has a lot of information about the situation, but the key line to confirm dnf caused the OOM event, is:

[ 1156.249100] Out of memory: Killed process 1538 (dnf) total-vm:638020kB, anon-rss:290432kB, file-rss:0kB, shmem-rss:0kB, UID:0 pgtables:1244kB oom_score_adj:0

Many of the OS images provided by GCP and other cloud providers, often do not provide a swap device which is fine for the larger instances but may be required on the smaller memory instances.

To resolve the situation, create a swap device for the instance. The following adds 1GB which is typically enough for the dnf and yum commands.

sudo fallocate -l 1G /swapfile
sudo mkswap /swapfile
sudo chmod 0600 /swapfile
sudo swapon /swapfile

Note: The above is not permanent, so you’ll want to add an entry to the /etc/fstab to ensure the swap device is added on each boot, eg:

/swapfile none                    swap    defaults        0 0

Into the 3MF Specification Wilderness: Reading 1000+ Pages of Specifications

Into the 3MF Specification Wilderness: Reading 1000+ Pages of Specifications

Series: Building lib3mf-rs

This post is part of a 5-part series on building a comprehensive 3MF library in Rust:

  1. Part 1: My Journey Building a 3MF Native Rust Library from Scratch
  2. Part 2: The Library Landscape - Why Build Another One?
  3. Part 3: Into the 3MF Specification Wilderness - Reading 1000+ Pages of Specifications
  4. Part 4: Design for Developers - Features, Flags, and the CLI
  5. Part 5: Reflections and What’s Next - Lessons from Building lib3mf-rs

“How hard can it be? It’s just a file format.”

That’s what I thought before I started reading the 3MF specifications. After reading, re-reading, and getting AI to help summarize and dig deeper into the interpretations and understandings, I was ready to begin.

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How To Install and Boot VMWare VSphere/ESXi from Persistent Memory (or not)

How To Install and Boot VMWare VSphere/ESXi from Persistent Memory (or not)

In a previous post I described how to install and boot Linux using only Persistent Memory, no SSDs are required. For this follow on post, I attempted to install VMWare VSphere/ESXi v7.0u2 onto the persistent memory.

TL;DR - It doesn’t work. The installer doesn’t list the PMem devices, and I was unable to find a way to manually select the PMem device(s).

I assume you followed the previous post to configure sector namespaces that we’ll use to install ESXi.

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Linux Kernel 6.10 is Released: This is What's New for Compute Express Link (CXL)

Linux Kernel 6.10 is Released: This is What's New for Compute Express Link (CXL)

The Linux Kernel 6.10 release brings several improvements and additions related to Compute Express Link (CXL) technology.

Here is the detailed list of all commits merged into the 6.10 Kernel for CXL and DAX. This list was generated by the Linux Kernel CXL Feature Tracker .

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