Software
What is Reserved Space and Why Does it Matter? Reserved filesystem space refers to the percentage of total disk space that is kept unused and allocated for root users only. This space cannot be used by regular users or processes and serves a vital purpose. Having sufficient reserved space enables critical system functions and emergency…
Enabling Kernel Features for Cloud Workloads The Linux and Unix-like kernels offer advanced control group (cgroup) functionality for limiting, prioritizing, accounting for, and isolating CPU, memory, disk I/O, network, and other resources for workloads. Configuring cgroups allows setting resource limits, guarantees resource minimums, divides resources proportionally, and defines hard and soft caps per workload. Namespaces…
Understanding Containers and Virtual Machines Containers and virtual machines are two virtualization technologies that allow multiple workloads to run on a single Linux or Unix-like host. Containers virtualize at the operating system level by isolating processes and resources using features like namespaces and cgroups in the Linux kernel. This allows running multiple isolated container instances…
The Problem of Blocked Processes When a process makes a system call that blocks, it can lead to poor system performance and responsiveness. System calls like read(), write(), and open() may need to wait for I/O resources to become available before they can complete. During this wait time, the process is said to be “blocked”…
Understanding Kernel Deadlocks A kernel deadlock is a state where two or more processes are unable to proceed because each is waiting on another to release a needed resource. This creates a circular dependency that brings the kernel to a halt. Kernel deadlocks are caused by inconsistent lock ordering, race conditions, priority inversions, and resource…
Understanding Journaling and Metadata Integrity Journaling is a technique used by advanced file systems like Ext4 and XFS to provide faster recovery after an unexpected shutdown or crash. By tracking metadata changes in a separate journal before committing them to the main file system, journaling reduces corruption and lost data if the system loses power…
dd is a versatile Unix utility that allows copying data between files and devices. Understanding how to optimize dd performance by tuning parameters like block size can lead to much faster data transfer rates. Understanding dd and Block Sizes The dd utility copies data in blocks of bytes from an input to an output location….
Assessing Your Legacy Infrastructure The first step in migrating your legacy infrastructure to the cloud is performing a comprehensive assessment of your existing hardware, software, dependencies and pain points. This involves creating a detailed inventory of servers, storage systems, networking equipment, databases, applications, integration tools and any other components currently supporting your workloads. Document hostname,…
Updating Systems for Improved Security and Compatibility Maintaining up-to-date systems is critical for organizations to ensure security, stability, and compatibility with modern software and hardware. However, adopting new standards like filesystems, init systems, compilers, and more can require significant evaluation, planning, and coordinated efforts across teams. Evaluating New Standards for Adoption Assessing benefits of adopting…
Controlling Software Sprawl As software environments on Linux grow in complexity, effectively managing software sprawl becomes critical. Key strategies to control proliferation of software packages include: Using package managers like APT, Yum, or DNF to track installed packages – These tools log all software installed through repositories, enabling administrators to monitor and manage components. Building…