General

SRE Weekly Issue #402

A message from our sponsor, FireHydrant:

Signals is now available in beta. Sign up to experience the difference: Page teams, not services. Ingest inputs from any source. Bucket pricing based on usage. And one platform — ring to retro — finally.
https://firehydrant.com/blog/signals-beta-live/

Wow, this interactive tool for choosing SLOs is fun to play with! Dragging the sliders really gives you a feel for the math involved, and then you get a formula that you can actually use.

  Alex Ewerlöf

A riveting story of a service that was the victim of its own success, a potential solution, and then further challenges to overcome.

  Tanat Lokejaroenlarb — Adevinta

Here’s a classic example of “work as imagined” vs “work as done”, as health care workers struggle against difficult security constraints while trying to care for patients.

  Fred Hebert — summary
  Ross Koppel, Sean Smith, Jim Blythe, and Vijay Kothari — original paper

This article covers a lot of ground, touching on a lot of components of a successful SRE program, and even includes a code example for SLO calculation.

  Vishal Padghan — Squadcast

More on the weird EBS performance regression I linked to last week. Still no full explanation of what changed, but at least they have a solution (gp3 volumes).

  Dustin Brown — dolthub

After a massive 73-hour outage, Roblox set out to redesign their infrastructure to make that kind of incident much less likely. They’ve charted a path through several intermediate architectures, with the ultimate goal of active-active datacenters.

  Daniel Sturman, Max Ross, and Michael Wolf — Roblox

Now here’s one that really makes me think. I can’t really summarize it in a sentence, so just go read it.

  Lorin Hochstein

SRE Weekly Issue #401

A message from our sponsor, FireHydrant:

Join FireHydrant Dec.14 for a conversation about on-call culture and its effect on engineering organizations, featuring special guests from Outreach and Udemy. Gain a better understanding of what makes excellent on-call culture and how to implement practices to improve yours.
https://app.livestorm.co/firehydrant/better-incidents-winter-bonfire-inside-on-call?type=detailed

Maybe you’re thinking of skipping over “yet another article about blamelessness”? Don’t. This one has some great examples and stories and is well worth a read.

  Michael Hart

I’m definitely guilty of a couple of these.

  Code Reliant

New podcast relevant to our interests!

In this series, you’ll hear insightful conversations with engineers, product managers, co-founders and more, all about the debatable topic of incident management.

  Luis Gonzalez — incident.io

A puzzling performance regression in EBS volumes, seemingly reproducible across instances. Anyone else seeing anything like this?

  Dustin Brown — dolthub

This article presents a framework for scaling SRE teams by defining SRE processes, automating, and iterating.

   Stelios Manioudakis — DZone

Some tips on what makes a good alert and how to design your alerts to be actually useful, rather than just noise.

  Leon Adato — Kentik

Why would you want multiple different targets for the same SLO? Read this one to find out.

  Alex Ewerlöf

Conflict-free Replicated Data Types are powerful, but they have downsides explained in this article, so it’d be great if we could avoid them when possible.

  Zak Knill

SRE Weekly Issue #400

A message from our sponsor, FireHydrant:

How is FireHydrant building its alerting tool, Signals, to be robust, lightning-fast, and configurable to how YOU work? In this edition, of their Captain’s Log, they dive into CEL and how they’re using it to handle routing and logic.
https://firehydrant.com/blog/captains-log-how-were-leveraging-cel/

The network is not reliable. What are the implications and what can we do about it?

  Anadi Misra

Beyond a run-of-the-mill severity levels article, this one goes into a couple of common pitfalls.

  Jonathan Word

Some good tips in here, esp. the one about brevity.

  Ashley Sawatsky — Rootly

Subtitle:

Or, Eleven things we have learned as Site Reliability Engineers at Google

   Adrienne Walcer, Kavita Guliani, Mikel Ward, Sunny Hsiao, and Vrai Stacey — Google

Good lessons to learn here that apply more broadly than just EKS.

  Christian Alexánder Polanco Valdez — Adevinta

This article is about project management, but a lot of the skills discussed apply to aspects of SRE at Staff+ levels.

  Sannie Lee — Thoughtworks (via martinfowler.com)

Now this is more like it: there’s a healthy does of skepticism woven through this article, including things genAI probably won’t be good for, and potential pitfalls.

  Jesse Robbins — Heavybit

There are two different ways of alerting on SLOs, for two very different audiences, as explained in this article. Ostensibly this is a product feature announcement, but you don’t need to be using the product to get a lot out of this.

  Fred Hebert — Honeycomb
  Full disclosure: Honeycomb is my employer.

SRE Weekly Issue #399

A message from our sponsor, FireHydrant:

Severity levels help responders and stakeholders understand the incident impact and set expectations for the level of response. This can mean jumping into action faster. But first, you have to ensure severity is actually being set. Here’s one way.
https://firehydrant.com/blog/incident-severity-why-you-need-it-and-how-to-ensure-its-set/

This research paper summary goes into Mode Error and the dangers of adding more features to a system in the form of modes, especially if the system can change modes on its own.

  Fred Hebert (summary)
  Dr. Nadine B. Sarter (original paper)

Cloudflare suffered a power outage in one of the datacenters housing their control and data planes. The outage itself is intriguing, and in its aftermath, Cloudflare learned that their system wasn’t as HA as they thought.

Lots of great lessons here, and if you want more, they posted another incident writeup recently.

   Matthew Prince — Cloudflare

Separating write from read workloads can increase complexity but also open the door to greater scalability, as this article explains.

  Pier-Jean Malandrino

Covers four strategies for load shedding, with code examples:

  • Random Shedding
  • Priority-Based Shedding
  • Resource-Based Shedding
  • Node Isolation

  Code Reliant

Lots of juicy details about the three outages, including a link to AWS’s write-up of their Lambda outage in June.

  Gergely Orosz

The diagrams in this article are especially useful for understanding how the circuit-breaker pattern works.

  Pier-Jean Malandrino

This one’s about how on-call can go bad, and how to structure your team’s on-call so to be livable and sustainable.

  Michael Hart

Execs cast a big shadow in an incident, so it’s important to have a plan for how to communicate with them, as this article explains.

  Ashley Sawatsky — Rootly

SRE Weekly Issue #398

A message from our sponsor, FireHydrant:

“Change is the essential process of all existence.” – Spock
It’s time for alerting to evolve. Get a first look at how incident management platform FireHydrant is architecting Signals, its native alerting tool, for resilience in the Signals Captain’s Log.
https://firehydrant.com/blog/captains-log-a-first-look-at-our-architecture-for-signals/

A cardiac surgeon draws lessons from the Tenerife commercial airline disaster and applies them to communication in the operating room.

  Dr. Rob Poston

Creating an incident write-up is an expensive investment. This article will tell you why it’s worthwhile.

  Emily Ruppe — Jeli

The optimism and pessimism in this article are about the likelihood of contention and conflicts between actors in a distributed system, and it’s a fascinating way of looking at things.

  Marc Brooker

Here is a guide for how to be an effective Incident Commander and get things fixed as quickly as possible as part of an efficient Incident Management process.

  Jonathan Word

The four concepts are Rebound, Robustness, Graceful Extensibility, and Sustained Adaptability, and this research paper summary explains each concept.

  Fred Hebert (summary)
  Dr. David Woods (original paper)

Apache Beam played a pivotal role in revolutionizing and scaling LinkedIn’s data infrastructure. Beam’s powerful streaming capabilities enable real-time processing for critical business use cases, at a scale of over 4 trillion events daily through more than 3,000 pipelines.

  Bingfeng Xia and Xinyu Liu — LinkedIn

Meta’s SCARF tool automatically scans for unused (dead) code and creates pull requests for their removal, on a daily basis.

  Will Shackleton, Andy Pincombe, and Katriel Cohn-Gordon — Meta

Netflix built a system that detects kernel panics in k8s nodes and annotates the resulting orphaned pods so that it’s clear what happened to them.

  Kyle Anderson — Netflix

This upcoming webinar will cover a range of topics around resilience engineering and incident response, with two big names we’ve seen in many past issues: Chris Evans (incident.io) and Courtney Nash (Verica).

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