Linux Kernel Secrets Revealed

00:00 The kernel you don't know 02:28 What the kernel actually controls 05:25 Swappiness: the parameter everyone gets wrong 07:58 VFS cache pressure and dirty pages 11:13 Transparent Huge Pages: not what you think 13:03 KSM, PSI, and max_map_count 14:49 Autogroup and CPU governors 18:50 CPU mitigations: security vs performance 21:06 Tickless kernel and RCU 25:02 I/O scheduler: choose the right one 27:53 Zswap, read-ahead, and kernel forensics 32:40 You're in control: don't accept the defaults Important: If you really want to follow this video properly and understand the topic in depth, read the full written guide: https://youtux.org/Kernel%20Secrets.html Your distro made hundreds of kernel decisions for you. Here's how to take them back. Most Linux users have never touched the kernel beyond accepting whatever their distro shipped. But the kernel exposes hundreds of runtime parameters — and some of them will fundamentally change how your system feels and performs. In this video: every command, every config file, every trade-off. No hand-waving. → vm.swappiness, vfs_cache_pressure, dirty_ratio → Transparent Huge Pages (THP): always / madvise / never → Kernel Same-page Merging (KSM) for VMs and containers → Pressure Stall Information (PSI): real kernel telemetry → Scheduler autogroup and CPU governors (schedutil, performance, powersave) → Spectre/Meltdown mitigations and their real performance cost → Tickless kernel (NO_HZ), RCU stall timeout → I/O schedulers: mq-deadline, Kyber, BFQ, none → Zswap with LZ4/Zstandard compression → Read-ahead tuning and kernel counter forensics → max_map_count: the silent killer for Proton, Elasticsearch, Java RESOURCES ──────────────────── References & Documentation Memory Management kernel.org/doc/html/latest/admin-guide/sysctl/vm.html — vm.swappiness, vm.vfs_cache_pressure, vm.dirty_ratio, vm.max_map_count kernel.org/doc/html/latest/mm/transhuge.html — Transparent Huge Pages kernel.org/doc/html/latest/mm/ksm.html — Kernel Same-page Merging CPU & Scheduling kernel.org/doc/html/latest/admin-guide/pm/cpufreq.html — CPU frequency governors kernel.org/doc/html/latest/admin-guide/hw-vuln/index.html — CPU security mitigations kernel.org/doc/html/latest/timers/no_hz.html — Tickless kernel (NO_HZ) kernel.org/doc/html/latest/RCU/index.html — RCU Storage & I/O kernel.org/doc/html/latest/block/bfq-iosched.html — BFQ I/O scheduler kernel.org/doc/html/latest/mm/zswap.html — Zswap Pressure Stall Information kernel.org/doc/html/latest/accounting/psi.html — PSI Community references wiki.archlinux.org/title/Sysctl wiki.archlinux.org/title/CPU_frequency_scaling wiki.archlinux.org/title/Zswap wiki.gentoo.org/wiki/Kernel/Gentoo_Kernel_Configuration_Guide