codebase Archives

Tech Optimizer

April 5, 2026

Linux 7.0 Cuts PostgreSQL Performance in Half

An AWS engineer reported a significant drop in PostgreSQL throughput on Linux 7.0, with performance reduced to approximately half of its previous capability. Benchmark tests showed that the removal of the PREEMPT_NONE scheduling option was the main cause of this regression. On a 96-vCPU Graviton4 instance, throughput measured at just 0.51x compared to earlier kernel versions. Salvatore Dipietro from Amazon/AWS conducted benchmarking analysis of PostgreSQL 17, revealing that Linux 7.0 delivered only 0.51x the throughput of its predecessors. The root cause was traced to kernel commit 7dadeaa6e851, which eliminated PREEMPT_NONE as the default option, leading to increased contention due to the new PREEMPT_LAZY model. Profiling data indicated that 55% of CPU time is consumed by spinning in PostgreSQL’s spinlock, causing significant performance degradation. When a revert patch was applied, throughput rebounded to 1.94x the baseline. The decision to restrict preemption modes in Linux 7.0 aimed to address issues within the kernel's scheduling model. Dipietro proposed a patch to restore PREEMPT_NONE, but kernel developers suggested PostgreSQL adopt the rseq time slice extension instead. Database operators running PostgreSQL on Linux face potential performance reductions with the upgrade to Linux 7.0.

Winsage

March 31, 2026

Speechify Launches with On-Device Voice AI for 1B+ Windows Users Worldwide

Speechify has launched a Windows application featuring real-time text-to-speech and speech-to-text functionality, allowing for both cloud-based and on-device processing. On-device processing ensures user voice data remains secure on the machine. The application utilizes the Windows ML stack and platform APIs to operate across x64 and Arm64 architectures, leveraging Qualcomm’s Snapdragon technology for enhanced performance. The ONNX Runtime's QNN execution provider facilitates real-time transcription on Snapdragon laptops, enabling a split encoder-decoder architecture that optimizes processing. The application includes features like system-wide shortcuts, auto-pasting of transcribed text, OCR functionality, and secure data handling through Windows DPAPI. The Speechify Windows application is available for x64 and Arm64 devices via the Microsoft Store.

AppWizard

March 19, 2026

New Perseus Android Banking Malware Monitors Notes Apps to Extract Sensitive Data

Cybersecurity researchers have identified a new family of Android malware called Perseus, designed for device takeovers and financial fraud. It utilizes Accessibility-based remote sessions for real-time monitoring and interaction with infected devices, particularly targeting Turkey and Italy. Perseus monitors user notes to extract personal or financial information and is distributed through dropper applications via phishing websites. It expands on the codebase of previous malware like Phoenix and employs disguises as IPTV services to reduce user suspicion. Once operational, it performs overlay attacks and captures keystrokes to steal credentials from financial applications. The malware allows operators to issue commands through a command-and-control panel, enabling various malicious actions, including capturing note content and initiating remote visual streams. Perseus also conducts environment checks to evade detection and ensure it operates on legitimate devices.

AppWizard

March 18, 2026

ChatGPT’s free tier gets GPT 5.4 mini model with improved coding capabilities

OpenAI has introduced the GPT 5.4 mini and nano models, making advanced AI capabilities accessible to free users of the ChatGPT platform. The GPT 5.4 mini operates more than twice as fast as its predecessor and closely matches the performance of the larger GPT 5.4 model in key evaluations. These models are designed for environments where latency is critical, excelling in coding, reasoning, multimodal understanding, and tool utilization. The GPT 5.4 mini is available in ChatGPT’s free and Go tiers, as well as in OpenAI’s API and Codex, while the nano variant is accessible exclusively through the API, both at lower costs than the original GPT 5.4 model.

AppWizard

March 13, 2026

Patch Me If You Can: AI Codemods for Secure-by-Default Android Apps

Meta’s Product Security team has developed a strategy to enhance mobile security through two main initiatives: creating secure-by-default frameworks that make secure Android OS APIs more accessible for developers, and utilizing generative AI to automate the migration of existing code to these frameworks. This approach allows for efficient large-scale updates and the ability to propose, validate, and submit security patches across millions of lines of code.