iowait (wait, wa, %iowait, wait%, or I/O wait) is often displayed by command-line Linux system monitoring tools such as top, sar, atop, and others. On its own, it’s one of many performance stats that provide us insight into Linux system performance. I/O wait came up in a recent discussion with a new client. During our support […]
Raspberry Pi Performance: Add ZRAM and these Kernel Parameters
Previously, I published a Pinebook Pro review article on this blog. Similar to the Pinebook Pro, the Raspberry Pi and, more recently, the Raspberry Pi 4 are also ARM-based. With good results, I’ve applied some of the optimizations mentioned in that previous article to the Raspberry Pi 4. I wanted to share these tweaks and […]
Linux server performance: Is disk I/O slowing your application?
If your Linux server is bogged down, your first step may often be to use the top command in the terminal to check load averages. However, there are times when top shows very high load averages even with low CPU ‘us’ (user) and high CPU ‘id’ (idle) percentages. This is the case in the video […]
Your Web Host Doesn’t Want You To Read This: Benchmark Your VPS
Aug 13th, 2023: added Yet-another-bench-script benchmarking tool. Sept 27th, 2021: Added link to a great list of command-line benckmark scripts. June 17th, 2019: Added instructions for network speed test using speedtest-cli script. Nov 2nd, 2016: Included quick dd commands to check cached vs. uncached read performance. This article will highlight using the ‘dd’ Unix command […]
Increase Performance and lifespan of SSDs & SD Cards
SSDs (solid-state drives) and SD (Secure Digital) cards have a limited number of writes before they wear out. To get the most out of this storage type, let’s investigate, then make a few adjustments to maximize the life of your SSDs and SD cards. This article has been refreshed from 6 years ago. Using iotop […]
Linux: ncdu and mc to manage large directories
Creating, modifying, and deleting files are everyday tasks performed in any operating system, even more so by Sysadmins, Developers, and Programmers. For the most part, these tasks are fast enough when managing a handful of files. However, on Linux and especially with servers, you may at some time have to manage millions or even billions […]
What to buy for your Raspberry Pi 4
Over the past year, the prices of Raspberry Pi 4 boards have skyrocketed to $200, $300 and even $400! If you don’t already have one, you may want to look into alternatives. Such as used Lenovo, Dell and HP micro and nano PCs from eBay. Currently, I’m using the ThinkCentre M73 (replaced broken link: ThinkCentre […]
2100 HDD0 initialization error 1
I’ve noticed an issue on a few IBM/Lenovo Thinkpads. When you install an SSD drive, a reboot or restart from the OS does not work. When you reboot, instead opening the boot partition, it throws this error: 2100 HDD0 initialization error 1 Other than avoiding reboot and using shutdown instead, the only solution I’ve found […]