Practical use of sysctl

I got a general question about sysctl
. I understand how I can view and change kernel parameters but I'm struggling to think of parameters I might want to tweak. The video in chapter 25 shows how to change kernel.pid_max
but that doesn't seem particularly useful (on my Fedora PC it's set to 4194304, which seems more than enough).
I looked into kernel.ctrl-alt-del
and kernel.hostname
. On my system kernel.ctl-alt-del
is set to 0, which means the Ctrl-Alt-Del behaviour is managed by the init system. Changing the value to 1 didn't change its behaviour.
Next, I permanently changed my system's hostname by adding a file under /etc/sysctl.d/. This worked, and I was very proud of myself. However, when I cat /etc/hostname I am still seeing the old hostname. That makes me wonder why I would want change the hostname via sysctl
. Simply updating /etc/hostname seems the right way to do this.
In short, I'm looking for some practical examples. Do any of you use sysctl
to tweak settings?
Comments
-
There are many parameters that include memory management and also networking properties. Take a look in /proc/sys/vm and /proc/sys/net/ipv4 for example. On my system there are over 900 entries in /proc/sys
1 -
Thanks for the quick response. I think you are the gentleman in the video? (I'm sure I've seen the user name coop in one of the videos).
I've dived into /proc/sys/vm/swappiness and it's al starting to sink in now, so thanks again for your reply.
0 -
yes that's me. I'm a little older than the avatar image here
1
Categories
- All Categories
- 51 LFX Mentorship
- 104 LFX Mentorship: Linux Kernel
- 576 Linux Foundation IT Professional Programs
- 304 Cloud Engineer IT Professional Program
- 125 Advanced Cloud Engineer IT Professional Program
- 53 DevOps Engineer IT Professional Program
- 61 Cloud Native Developer IT Professional Program
- 5 Express Training Courses
- 5 Express Courses - Discussion Forum
- 2.1K Training Courses
- 19 LFC110 Class Forum
- 7 LFC131 Class Forum
- 27 LFD102 Class Forum
- 158 LFD103 Class Forum
- 20 LFD121 Class Forum
- 1 LFD137 Class Forum
- 61 LFD201 Class Forum
- 1 LFD210 Class Forum
- LFD210-CN Class Forum
- 1 LFD213 Class Forum - Discontinued
- 128 LFD232 Class Forum
- LFD237 Class Forum
- 23 LFD254 Class Forum
- 611 LFD259 Class Forum
- 105 LFD272 Class Forum
- 1 LFD272-JP クラス フォーラム
- 1 LFD273 Class Forum
- 2 LFS145 Class Forum
- 25 LFS200 Class Forum
- 739 LFS201 Class Forum
- 1 LFS201-JP クラス フォーラム
- 11 LFS203 Class Forum
- 75 LFS207 Class Forum
- 300 LFS211 Class Forum
- 54 LFS216 Class Forum
- 47 LFS241 Class Forum
- 41 LFS242 Class Forum
- 37 LFS243 Class Forum
- 11 LFS244 Class Forum
- 37 LFS250 Class Forum
- 1 LFS250-JP クラス フォーラム
- LFS251 Class Forum
- 141 LFS253 Class Forum
- LFS254 Class Forum
- 1.1K LFS258 Class Forum
- 10 LFS258-JP クラス フォーラム
- 93 LFS260 Class Forum
- 132 LFS261 Class Forum
- 33 LFS262 Class Forum
- 80 LFS263 Class Forum
- 15 LFS264 Class Forum
- 11 LFS266 Class Forum
- 18 LFS267 Class Forum
- 18 LFS268 Class Forum
- 23 LFS269 Class Forum
- 203 LFS272 Class Forum
- 1 LFS272-JP クラス フォーラム
- LFS274 Class Forum
- LFS281 Class Forum
- 236 LFW211 Class Forum
- 172 LFW212 Class Forum
- 7 SKF100 Class Forum
- SKF200 Class Forum
- 903 Hardware
- 219 Drivers
- 74 I/O Devices
- 44 Monitors
- 116 Multimedia
- 209 Networking
- 101 Printers & Scanners
- 85 Storage
- 763 Linux Distributions
- 88 Debian
- 66 Fedora
- 15 Linux Mint
- 13 Mageia
- 24 openSUSE
- 142 Red Hat Enterprise
- 33 Slackware
- 13 SUSE Enterprise
- 357 Ubuntu
- 479 Linux System Administration
- 41 Cloud Computing
- 70 Command Line/Scripting
- Github systems admin projects
- 95 Linux Security
- 78 Network Management
- 108 System Management
- 49 Web Management
- 68 Mobile Computing
- 23 Android
- 30 Development
- 1.2K New to Linux
- 1.1K Getting Started with Linux
- 538 Off Topic
- 131 Introductions
- 217 Small Talk
- 22 Study Material
- 826 Programming and Development
- 278 Kernel Development
- 514 Software Development
- 928 Software
- 260 Applications
- 184 Command Line
- 3 Compiling/Installing
- 76 Games
- 316 Installation
- 61 All In Program
- 61 All In Forum
Upcoming Training
-
August 20, 2018
Kubernetes Administration (LFS458)
-
August 20, 2018
Linux System Administration (LFS301)
-
August 27, 2018
Open Source Virtualization (LFS462)
-
August 27, 2018
Linux Kernel Debugging and Security (LFD440)