VMware Player and VirtualBox are two free virtualization platforms that run on Linux hosts. Both offer full virtualization capabilities, though they differ in performance characteristics, ease of use, and licensing models. This guide covers installation, basic operation, and removal on current Fedora releases. VMware Player Install VMware Player Download the installer bundle from VMware’s website….
SSH performance is constrained by cipher choice, especially for large file transfers over high-bandwidth links where CPU becomes the bottleneck. Selecting the right cipher, key exchange algorithm, and compression settings can yield substantial throughput improvements. Current Cipher Landscape Modern OpenSSH (7.4+) has deprecated or removed weak ciphers. Here’s what’s viable today: Secure and performant: chacha20-poly1305@openssh.com…
WordPress performance depends on three complementary caching layers: PHP bytecode caching (OPcache), page caching (WP Super Cache), and asset optimization (Autoptimize). Combined properly, they’ll cut your Time to First Byte in half and significantly improve Core Web Vitals. Enable OPcache in PHP OPcache caches compiled PHP bytecode in shared memory, eliminating parse and compile overhead…
Emacs startup is slow. If you’re using it for quick edits alongside other tools, waiting 2-3 seconds every time becomes friction. Heavy mode configurations, lazy loading chains, and initialization hooks add up fast. The server/client architecture solves this: start an Emacs server once, then spawn lightweight clients that connect almost instantly. Your first edit waits…
Benchmarks exist to answer one question: how fast can this system process data? The AMPLab Big Data Benchmark, developed by UC Berkeley, became a foundational effort to answer that question systematically across different distributed query engines. The Benchmark’s Original Scope The AMPLab benchmark evaluated five systems circa 2013: Redshift – Amazon’s columnar data warehouse (built…
Fedora is a cutting-edge distribution sponsored by Red Hat that serves as a testing ground for technologies eventually stabilized in RHEL. This guide covers essential infrastructure, system administration, and desktop tools for modern Fedora systems, with practical installation and usage examples. Desktop Environment Setup GNOME Configuration Modern GNOME desktops (GNOME 40+) use dconf for configuration,…
VNC provides graphical remote access to Linux servers. For security, tunnel VNC traffic through SSH rather than expose it directly to the network. This guide covers Windows client setup with SSH tunneling. Prerequisites Windows client: SSH client: Native OpenSSH (built into Windows 10/11) or PuTTY VNC viewer: RealVNC Viewer, TigerVNC Viewer, or TightVNC Viewer Linux…
Self-hosting a photo gallery gives you control over your content. If you want to skip database management entirely, a handful of PHP solutions still work—though most are unmaintained. This post covers what’s still functional, where the limits are, and when you should choose something else instead. Static File-Based Gallery Scripts Single File PHP Gallery Status:…
Choosing the right cloud storage service requires understanding how each platform handles data consistency. This post covers the current consistency guarantees from the three major providers and how they affect your application design. Amazon S3 S3 is a key-based object store built for Internet-scale workloads. The consistency model is now straightforward across all operations. S3…
RAID0 (striping) on enterprise RAID controllers like Broadcom MegaRAID is used to expose multiple disks as a single logical volume with no redundancy. This configuration is appropriate only for performance-critical workloads where data loss from a single disk failure is acceptable, or for temporary/cache storage. This guide covers the full setup process on servers with…
NFSv3 uses multiple RPC services, each requiring its own port assignment. Without explicit configuration, rpcbind assigns random high ports to four critical services, making firewall rules unmaintainable. Modern deployments should prioritize NFSv4 with Kerberos, but legacy NFSv3 environments remain common enough to warrant proper port management. The NFS service stack includes seven RPC programs: Service…
SSH port forwarding lets you tunnel network traffic through an encrypted connection, making it essential for accessing services on restricted networks, exposing local services safely, or routing traffic through a jump host. This guide covers the three main types and production-ready practices. Local Forwarding Local forwarding listens on your local machine and relays connections through…
The proprietary fglrx driver reached end-of-life in 2015 and is incompatible with current Fedora releases. For modern AMD GPUs, use AMDGPU—AMD’s actively maintained open-source driver that supports Wayland, current kernel versions, and both desktop and compute workloads. GPU Compatibility RDNA and newer (RX 5000 series and later): AMDGPU is required and fully supported. GCN-era Radeons…
Xen remains in production use at scale across AWS EC2, Citrix Hypervisor, and various cloud providers, though KVM has become the default hypervisor for most Linux distributions. If you’re operating a Xen environment, Dom0 resource management is critical to system stability. Why Dom0 Resource Management Matters Dom0 performance directly affects your entire virtualized infrastructure. Since…
This guide sets up OpenLDAP for centralized authentication and NFS with automount to provide unified home directories across a cluster. The setup uses modern OpenLDAP backends and current NFS4 best practices. System Environment Server: LDAP and NFS: 10.0.0.2, Fedora 41 x86_64 Base DN: dc=lgcpu1 Clients: Range: 10.0.0.1/24, Fedora 41 x86_64 LDAP Server Setup Package Installation…
Measuring time accurately matters for performance profiling, benchmarking, and latency-sensitive applications. Linux provides several APIs with different tradeoffs in resolution, overhead, and reliability. Understanding which to use prevents subtle bugs in production code. POSIX Time APIs: gettimeofday and clock_gettime gettimeofday() and clock_gettime() are the standard POSIX calls for reading system time. gettimeofday() returns seconds and…
John Ousterhout, a professor of computer science at Stanford, maintains a collection of “Favorite Sayings” grounded in decades of building real systems—RAMCloud, Tcl, and extensive work in distributed systems. These aren’t abstract principles. They’re lessons that apply directly to the work of building, debugging, and shipping software at scale. Optimize After Measurement, Not Before The…
Jeff Dean’s foundational work on large-scale distributed systems at Google established performance metrics that remain essential for making sound architectural decisions. While absolute numbers shift with hardware advances, the relative orders of magnitude have proven remarkably stable. These latency figures represent the raw cost of fundamental operations. Understanding them prevents decisions that seem reasonable in…
MapReduce is a foundational distributed computing model, but it’s no longer the default choice for new projects. Hadoop’s MapReduce (via YARN in Hadoop 2.x+) remains production-stable and useful for specific scenarios, while Apache Spark, Flink, and cloud-native services handle most modern workloads more efficiently. When MapReduce Still Makes Sense Use MapReduce if you’re: Maintaining existing…
Modern MediaWiki installations should prioritize responsive design, but you may still need explicit device-based skin switching for specific use cases. This guide covers both approaches and how to implement them correctly. Responsive Skins: The Recommended Approach The default solution is using a responsive skin that adapts automatically to screen size without separate configuration. Vector 2022…