Ardent Performance Computing
kubernetes
Openclaw is Spam, Like Any Other Automated Email
Open Source communities are trying to quickly adapt to the present rapid advances in technology. I would like to propose some clarity around something that should be common sense. Automated emails are spam. They always have been. Openclaw (and whatever new thing surfaces this summer) is no different. Policies saying automated emails/messages are banned – … Continue reading
The Scott Shambaugh Situation Clarifies How Dumb We Are Acting
Edit: related blog published Feb 22 – Openclaw is Spam, Like Any Other Automated Email My personal blog here is dedicated to tech geek material, mostly about databases like postgres. I don’t get political, but at the moment I’m so irritated that I’m making the extraordinary exception to veer into the territory of flame-war opinionating… This … Continue reading
KubeCon 2025: Bookmarks on Memory and Postgres
Just got home from KubeCon. One of my big goals for the trip was to make some progress in a few areas of postgres and kubernetes – primarily around allowing more flexible use of the linux page cache and avoiding OOM kills with less hardware overprovisioning. When I look at Postgres on Kubernetes, I think … Continue reading
Testing CloudNativePG Preferred Data Durability
This is the third post about running Jepsen against CloudNativePG. Earlier posts: First: shout out to whoever first came up with Oracle Data Guard Protection Modes. Designing it to be explained as a choice between performance, availability and protection was a great idea. Yesterday’s blog post described how the core of all data safety is copies of … Continue reading
Data Safety on a Budget
Many experienced DBAs joke that you can boil down the entire job to a single rule of thumb: Don’t lose your data. It’s simple, memorable, and absolutely true – albeit a little oversimplified. Mark Porter’s Cultural Hint “The Onion of our Requirements” conveys the same idea with a lot more accuracy: We need to always make sure we … Continue reading
Losing Data is Harder Than I Expected
This is a follow‑up to the last article: Run Jepsen against CloudNativePG to see sync replication prevent data loss. In that post, we set up a Jepsen lab to make data loss visible when synchronous replication was disabled — and to show that enabling synchronous replication prevents it under crash‑induced failovers. Since then, I’ve been … Continue reading
Run Jepsen against CloudNativePG to see sync replication prevent data loss
Are you in the Pacific Northwest? Want to learn more about topics related to this blog? At 3:15p on Thu Nov 13 in KubeCon Atlanta, I’ll be speaking with Leonardo Cecchi about distributed systems theory applied to standard open source postgres cluster reconfigurations. Jepsen is a testing framework for distributed systems that verifies safety guarantees … Continue reading
Graviton2 versus Graviton4
Just a short post, because I thought this was pretty remarkable. Below, I have screenshots showing the CPU utilization of two AWS instances in us-west-2 which are running an identical workload. They are running the CloudNativePG playground, which is a production-like learning and testing environment (all running virtually inside the single ec2 instance, which can … Continue reading
Waiting for Postgres 18 – Docker Containers 34% Smaller
On February 25, 2025 Christoph Berg committed the patch: This closed Debian bug 927182 which had been opened in April 2019 by Laurence Parry. That bug had raised concerns over the significant size increase of adding LLVM as a requirement to support Postgres JIT functionality. Postgres supports packaging LLVM as a separate optional package without … Continue reading
Testing loadBalancerSourceRanges with CloudNativePG on Azure Kubernetes
This option didn’t seem super widely documented from my initial searches online; it should be able to basically enforce layer 4 ingress/firewall rules at the individual service level. This is a quick test to check if it works. Steps were generated with ChatGPT, and mostly worked. It missed Azure provider registration, but I figure that … Continue reading
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contact: schneider @ ardentperf.com
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