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Documentation / sysctl / README


Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 EST.

1	Documentation for /proc/sys/		kernel version 2.2.10
2		(c) 1998, 1999,  Rik van Riel <riel@nl.linux.org>
3	
4	'Why', I hear you ask, 'would anyone even _want_ documentation
5	for them sysctl files? If anybody really needs it, it's all in
6	the source...'
7	
8	Well, this documentation is written because some people either
9	don't know they need to tweak something, or because they don't
10	have the time or knowledge to read the source code.
11	
12	Furthermore, the programmers who built sysctl have built it to
13	be actually used, not just for the fun of programming it :-)
14	
15	==============================================================
16	
17	Legal blurb:
18	
19	As usual, there are two main things to consider:
20	1. you get what you pay for
21	2. it's free
22	
23	The consequences are that I won't guarantee the correctness of
24	this document, and if you come to me complaining about how you
25	screwed up your system because of wrong documentation, I won't
26	feel sorry for you. I might even laugh at you...
27	
28	But of course, if you _do_ manage to screw up your system using
29	only the sysctl options used in this file, I'd like to hear of
30	it. Not only to have a great laugh, but also to make sure that
31	you're the last RTFMing person to screw up.
32	
33	In short, e-mail your suggestions, corrections and / or horror
34	stories to: <riel@nl.linux.org>
35	
36	Rik van Riel.
37	
38	==============================================================
39	
40	Introduction:
41	
42	Sysctl is a means of configuring certain aspects of the kernel
43	at run-time, and the /proc/sys/ directory is there so that you
44	don't even need special tools to do it!
45	In fact, there are only four things needed to use these config
46	facilities:
47	- a running Linux system
48	- root access
49	- common sense (this is especially hard to come by these days)
50	- knowledge of what all those values mean
51	
52	As a quick 'ls /proc/sys' will show, the directory consists of
53	several (arch-dependent?) subdirs. Each subdir is mainly about
54	one part of the kernel, so you can do configuration on a piece
55	by piece basis, or just some 'thematic frobbing'.
56	
57	The subdirs are about:
58	abi/		execution domains & personalities
59	debug/		<empty>
60	dev/		device specific information (eg dev/cdrom/info)
61	fs/		specific filesystems
62			filehandle, inode, dentry and quota tuning
63			binfmt_misc <Documentation/admin-guide/binfmt-misc.rst>
64	kernel/		global kernel info / tuning
65			miscellaneous stuff
66	net/		networking stuff, for documentation look in:
67			<Documentation/networking/>
68	proc/		<empty>
69	sunrpc/		SUN Remote Procedure Call (NFS)
70	vm/		memory management tuning
71			buffer and cache management
72	user/		Per user per user namespace limits
73	
74	These are the subdirs I have on my system. There might be more
75	or other subdirs in another setup. If you see another dir, I'd
76	really like to hear about it :-)
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