Your Linux kernel has been screaming at you since boot. You just never listened. Every single second, your kernel writes messages into a 128KB ring buffer — hardware failures, driver crashes, security warnings, OOM kills. Most of them disappear before anyone reads them. Here's what's happening under the hood: The kernel ring buffer is a circular log. When it fills up, new messages overwrite the oldest ones. No warning. No backup. Gone. Right now, on your machine: - dmesg | wc -l → probably alot of messages since boot - dmesg | grep -i error → dozens you never saw - dmesg | grep -i warn → hundreds you ignored The 8 log levels (KERN_EMERG → KERN_DEBUG) decide what shows on your console vs what stays buried. Most distros only surface level 4 and above. Everything else? Silent. If your server crashes at 3 AM because a disk controller failed, the warning was probably in dmesg 6 hours earlier. Overwritten. Unread. dmesg -T --level=err,warn | tail -50 -T gives human timestamps. --level filters the noise. Set up persistent logging (journalctl -k) or you're flying blind. Check the full visual breakdown of how the ring buffer works, from printk() to your terminal. Follow for more Linux internals that actually matter. thelinuxcamp.com
Linux Kernel Messages Overwritten in Ring Buffer
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the realistic impact is the disk I/O rate per operation...or we called it IOPS...u got a fancy GPU memory or whatsoever fancy RAM memory module...if your disk operation failed to capture the higher I/O rate per operation...means your performance hit the bottleneck... similar to your DIMM in server...if u choose the lower clock speed on DIMM...u r telling the server to use the lower clock speed not the higher clock speed in the memory module...
Infrastructure SaaS Founder | Creator of Dashmon.online | Systems & DevOps Engineer | Linux, Windows, Cloud & Automation
🟢 Filesystem Caching Explained for Infrastructure Engineers Style: calm explainer One of the most misleading Linux screenshots is the one where RAM looks “used” and someone assumes memory is being wasted. But Linux is deliberately aggressive with caching. Red Hat’s documentation explains that Linux uses available RAM for buffers and cache to speed up disk operations, and that page cache holds file and block-device data specifically to reduce disk reads. That means: 🔹 free RAM is often repurposed into useful cache 🔹 page cache improves read performance 🔹 cached memory is generally reclaimable if applications need it So high cached memory is often a sign the system is doing something smart, not something wrong. 💬 Engineer takeaway: Buffers and cache are usually not “wasted memory.” They are Linux turning spare RAM into I/O acceleration.
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