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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I often find myself confused by "upstream" and "downstream", in the context of software development. They bother me so much that I avoid using them in my own writing and I have to pause whenever I see them. In this post, I'll show a simple rule that helps you remember the difference: downstream adds …

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Modern CPUs operate significantly faster than memory. A 4.5 GHz x86_64 CPU operates 30 times faster than 6000 MHz DDR5 memory with CAS Latency 36. When accounting for latencies from the bus and memory coherency protocols, memory can be 100 times slower than registers. To mitigate this speed gap, CPUs use layers of …

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Given a non-decreasing array and a target value, we can find the target in logarithmic time using binary search. My first programming language was C++, and the C++ Standard Template Library (STL) provides two functions for this task: iterator lower_bound(first, last, value) returns the smallest index with a value …

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Problem Given an integer array A, in one step, remove all elements A[i] where A[i-1] > A[i]. Return the number of steps performed until A becomes a non-decreasing array. See examples at LeetCode 2289. Solution The naive approach executes steps one by one. Store integers in a Linked List. At each step, find all …

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Problem In a connected network consisting of N nodes, each node is connected to either one or two neighbors, forming a line topology. The task is to develop a program that runs on each node, calculating the total number of nodes in the network. Each node is aware of its neighboring nodes and can exchange messages with …

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