Having 12+ Years of Experience in Software Development
Prerequisites and Initial Setup This guide assumes a fresh Debian 12 (Bookworm) installation with root or sudo access. We’ll be setting up isolated SFTP users, each confined to their own directory, and ensuring they can execute PHP 8.2 scripts within their chroot environment. This is crucial for multi-developer workflows where code separation and controlled access […]
Understanding mpm_event and Thread Exhaustion Apache2’s `mpm_event` module, the default on Debian 12 Bookworm, is designed for high-concurrency environments by employing a hybrid approach: it uses worker threads to handle requests within each child process, but also a dedicated listener thread per child to manage the network socket and pass requests to worker threads. This […]
Understanding PostgreSQL Shared Buffers and Work Mem for High-Traffic Django Optimizing PostgreSQL 16’s `shared_buffers` and `work_mem` is paramount for Django applications experiencing heavy traffic. These two parameters directly influence how PostgreSQL caches data and handles sorting/hashing operations, respectively. Incorrect tuning can lead to excessive disk I/O, slow query execution, and ultimately, application unresponsiveness. This guide […]
Pre-Upgrade Assessment and Preparation Before initiating any production environment upgrade, a thorough assessment of the current Debian 11 (Bullseye) system and its CodeIgniter 4 application is paramount. This phase focuses on identifying potential compatibility issues, backing up critical data, and establishing a rollback strategy. Begin by documenting the exact versions of PHP, Apache/Nginx, MySQL/PostgreSQL, and […]
Prerequisites and Initial Setup This guide assumes a fresh Debian 12 (Bookworm) installation with root or sudo privileges. We’ll focus on a minimal setup to get a Perl Plack/PSGI application running efficiently behind Nginx, managed by Starman. This approach prioritizes performance and resource utilization, making it suitable for enterprise environments where every millisecond and megabyte […]
Understanding the ‘server reached pm.max_children’ Error The alert “server reached pm.max_children” from PHP-FPM is a critical indicator that your FastCGI Process Manager is unable to spawn new worker processes to handle incoming web requests. This typically occurs when the configured maximum number of child processes (pm.max_children) has been reached, and all existing children are busy […]
Prerequisites and Initial Assessment This guide details the process of upgrading Python from version 3.10 to 3.12 on an Ubuntu 22.04 LTS (Jammy Jellyfish) system, with a specific focus on safely re-linking Gunicorn virtual environments. This is a critical operation for maintaining production services, ensuring compatibility with newer libraries, and leveraging performance improvements in Python […]
Understanding the Bottlenecks for High Concurrency Handling 50,000 concurrent HTTP requests on a single Ubuntu 22.04 LTS server is a demanding task that pushes the limits of the operating system’s networking stack. The primary bottlenecks typically lie within the Linux kernel’s TCP/IP implementation, specifically in areas related to connection management, memory allocation for buffers, and […]
Prerequisites and Initial Setup This guide assumes a fresh Ubuntu 24.04 LTS server instance with root or sudo privileges. We’ll be setting up a production-ready environment for a Python FastAPI application served by Uvicorn, with Nginx acting as a reverse proxy. Ensure you have Python 3.10+ and pip installed. If not, you can install them […]
Prerequisites and Environment Setup Before embarking on the compilation of custom PHP 8.3 C extensions, ensure your Ubuntu 22.04 LTS system is adequately prepared. This involves installing essential development tools and libraries. A robust build environment is critical for a smooth compilation process and to avoid cryptic errors during the extension build. The primary dependencies […]