This week, I needed to install the Amazon SSM Agent and was surprised to find that GPG (GNU Privacy Guard) was the only way to verify the download. I had assumed that software downloads verification had largely transitioned to PKI (Public Key Infrastructure). This short post is a refresh on GPG. OpenPGP is an open …

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Hello! https://github.com/bcressey/bottlerocket/commits/debug-unified-fips/ https://github.com/bcressey/bottlerocket/commit/a2f3ef75b080d3cce1b077e9bc313bc0126c70c4

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While debugging memory bloat in a Go application recently, I found that removing the GOMEMLIMIT soft memory limit and disabling transparent huge pages partially mitigated the issue. However, I couldn't fully explain why these changes worked. So I thought why not ask the internet about it. A simplified memory bloat …

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It's a beautiful day, and it started with a simple code review: 1# tools/foo/main.go 2- fmt.Println("found it") 3+ log.Println("found it") The author explained the advantages of using a logging library over plain printf. The rationale was straightforward, so I approved the change without hesitation. …

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We started migrating from Amazon Linux 2 (AL2) to Amazon Linux 2023 (AL2023) a month ago. While testing workloads on AL2023 in the pre-production environment, I noticed slightly higher disk usage compared to the same workload on AL2. In this post, I'll share my investigation. AL2023 Has Less Free Disk Space with ext4, …

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Our Go programs recently triggered an alarm due to excessive panics. Panic is a Go runtime mechanism that halts execution. It got me thinking about different ways a Go program can die. I don't expect many - not like A Million Ways to Die in the West. In this post, we'll go through the various ways Go programs die. …

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As Amazon Linux 2 (AL2) approaches its End of Life on June 30, 2025, we have started migrating our container platform from AL2 to Bottlerocket. The migration encountered a few speed bumps. In this post, we'll examine one of them: missing container disk I/O stats. Why are container I/O dashboards blank? Since …

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I've been building a service for a month, and the day finally arrived when I had the artifact - an EC2 AMI. The AMI passed my "rigorous" manual tests so I launched 100 EC2 instances. Surprise! Around 28 instances failed to launch. What's going on? All failed instances were stuck in the …

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Given an array of numbers A, find out whether it contains a 1-3-2 pattern. A 1-3-2 pattern is a subsequence of three numbers, A[i], A[j] and A[k] such that i < j < k and A[i] < A[k] < A[j]. For clarity, let's call the 1-3-2 pattern the Bronze-Gold-Silver pattern. If A[j] is Gold, then we should consider the …

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Tony Hoare invented QuickSort in 1961. At the time of its publication, the best comparison-based sorting algorithm was merge sort. Merge sort divides an unordered array into two equally sized subarrays, sorts each subarray, and then merge the two subarrays to produce a sorted array. Merge sort is simple to understand. …

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