diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/sysctl |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/sysctl')
-rw-r--r-- | Documentation/sysctl/README | 75 | ||||
-rw-r--r-- | Documentation/sysctl/abi.txt | 54 | ||||
-rw-r--r-- | Documentation/sysctl/fs.txt | 150 | ||||
-rw-r--r-- | Documentation/sysctl/kernel.txt | 314 | ||||
-rw-r--r-- | Documentation/sysctl/sunrpc.txt | 20 | ||||
-rw-r--r-- | Documentation/sysctl/vm.txt | 104 |
6 files changed, 717 insertions, 0 deletions
diff --git a/Documentation/sysctl/README b/Documentation/sysctl/README new file mode 100644 index 000000000000..8c3306e01d52 --- /dev/null +++ b/Documentation/sysctl/README | |||
@@ -0,0 +1,75 @@ | |||
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/binfmt_misc.txt> | ||
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 | |||
73 | These are the subdirs I have on my system. There might be more | ||
74 | or other subdirs in another setup. If you see another dir, I'd | ||
75 | really like to hear about it :-) | ||
diff --git a/Documentation/sysctl/abi.txt b/Documentation/sysctl/abi.txt new file mode 100644 index 000000000000..63f4ebcf652c --- /dev/null +++ b/Documentation/sysctl/abi.txt | |||
@@ -0,0 +1,54 @@ | |||
1 | Documentation for /proc/sys/abi/* kernel version 2.6.0.test2 | ||
2 | (c) 2003, Fabian Frederick <ffrederick@users.sourceforge.net> | ||
3 | |||
4 | For general info : README. | ||
5 | |||
6 | ============================================================== | ||
7 | |||
8 | This path is binary emulation relevant aka personality types aka abi. | ||
9 | When a process is executed, it's linked to an exec_domain whose | ||
10 | personality is defined using values available from /proc/sys/abi. | ||
11 | You can find further details about abi in include/linux/personality.h. | ||
12 | |||
13 | Here are the files featuring in 2.6 kernel : | ||
14 | |||
15 | - defhandler_coff | ||
16 | - defhandler_elf | ||
17 | - defhandler_lcall7 | ||
18 | - defhandler_libcso | ||
19 | - fake_utsname | ||
20 | - trace | ||
21 | |||
22 | =========================================================== | ||
23 | defhandler_coff: | ||
24 | defined value : | ||
25 | PER_SCOSVR3 | ||
26 | 0x0003 | STICKY_TIMEOUTS | WHOLE_SECONDS | SHORT_INODE | ||
27 | |||
28 | =========================================================== | ||
29 | defhandler_elf: | ||
30 | defined value : | ||
31 | PER_LINUX | ||
32 | 0 | ||
33 | |||
34 | =========================================================== | ||
35 | defhandler_lcall7: | ||
36 | defined value : | ||
37 | PER_SVR4 | ||
38 | 0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO, | ||
39 | |||
40 | =========================================================== | ||
41 | defhandler_libsco: | ||
42 | defined value: | ||
43 | PER_SVR4 | ||
44 | 0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO, | ||
45 | |||
46 | =========================================================== | ||
47 | fake_utsname: | ||
48 | Unused | ||
49 | |||
50 | =========================================================== | ||
51 | trace: | ||
52 | Unused | ||
53 | |||
54 | =========================================================== | ||
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt new file mode 100644 index 000000000000..0b62c62142cf --- /dev/null +++ b/Documentation/sysctl/fs.txt | |||
@@ -0,0 +1,150 @@ | |||
1 | Documentation for /proc/sys/fs/* kernel version 2.2.10 | ||
2 | (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> | ||
3 | |||
4 | For general info and legal blurb, please look in README. | ||
5 | |||
6 | ============================================================== | ||
7 | |||
8 | This file contains documentation for the sysctl files in | ||
9 | /proc/sys/fs/ and is valid for Linux kernel version 2.2. | ||
10 | |||
11 | The files in this directory can be used to tune and monitor | ||
12 | miscellaneous and general things in the operation of the Linux | ||
13 | kernel. Since some of the files _can_ be used to screw up your | ||
14 | system, it is advisable to read both documentation and source | ||
15 | before actually making adjustments. | ||
16 | |||
17 | Currently, these files are in /proc/sys/fs: | ||
18 | - dentry-state | ||
19 | - dquot-max | ||
20 | - dquot-nr | ||
21 | - file-max | ||
22 | - file-nr | ||
23 | - inode-max | ||
24 | - inode-nr | ||
25 | - inode-state | ||
26 | - overflowuid | ||
27 | - overflowgid | ||
28 | - super-max | ||
29 | - super-nr | ||
30 | |||
31 | Documentation for the files in /proc/sys/fs/binfmt_misc is | ||
32 | in Documentation/binfmt_misc.txt. | ||
33 | |||
34 | ============================================================== | ||
35 | |||
36 | dentry-state: | ||
37 | |||
38 | From linux/fs/dentry.c: | ||
39 | -------------------------------------------------------------- | ||
40 | struct { | ||
41 | int nr_dentry; | ||
42 | int nr_unused; | ||
43 | int age_limit; /* age in seconds */ | ||
44 | int want_pages; /* pages requested by system */ | ||
45 | int dummy[2]; | ||
46 | } dentry_stat = {0, 0, 45, 0,}; | ||
47 | -------------------------------------------------------------- | ||
48 | |||
49 | Dentries are dynamically allocated and deallocated, and | ||
50 | nr_dentry seems to be 0 all the time. Hence it's safe to | ||
51 | assume that only nr_unused, age_limit and want_pages are | ||
52 | used. Nr_unused seems to be exactly what its name says. | ||
53 | Age_limit is the age in seconds after which dcache entries | ||
54 | can be reclaimed when memory is short and want_pages is | ||
55 | nonzero when shrink_dcache_pages() has been called and the | ||
56 | dcache isn't pruned yet. | ||
57 | |||
58 | ============================================================== | ||
59 | |||
60 | dquot-max & dquot-nr: | ||
61 | |||
62 | The file dquot-max shows the maximum number of cached disk | ||
63 | quota entries. | ||
64 | |||
65 | The file dquot-nr shows the number of allocated disk quota | ||
66 | entries and the number of free disk quota entries. | ||
67 | |||
68 | If the number of free cached disk quotas is very low and | ||
69 | you have some awesome number of simultaneous system users, | ||
70 | you might want to raise the limit. | ||
71 | |||
72 | ============================================================== | ||
73 | |||
74 | file-max & file-nr: | ||
75 | |||
76 | The kernel allocates file handles dynamically, but as yet it | ||
77 | doesn't free them again. | ||
78 | |||
79 | The value in file-max denotes the maximum number of file- | ||
80 | handles that the Linux kernel will allocate. When you get lots | ||
81 | of error messages about running out of file handles, you might | ||
82 | want to increase this limit. | ||
83 | |||
84 | The three values in file-nr denote the number of allocated | ||
85 | file handles, the number of unused file handles and the maximum | ||
86 | number of file handles. When the allocated file handles come | ||
87 | close to the maximum, but the number of unused file handles is | ||
88 | significantly greater than 0, you've encountered a peak in your | ||
89 | usage of file handles and you don't need to increase the maximum. | ||
90 | |||
91 | ============================================================== | ||
92 | |||
93 | inode-max, inode-nr & inode-state: | ||
94 | |||
95 | As with file handles, the kernel allocates the inode structures | ||
96 | dynamically, but can't free them yet. | ||
97 | |||
98 | The value in inode-max denotes the maximum number of inode | ||
99 | handlers. This value should be 3-4 times larger than the value | ||
100 | in file-max, since stdin, stdout and network sockets also | ||
101 | need an inode struct to handle them. When you regularly run | ||
102 | out of inodes, you need to increase this value. | ||
103 | |||
104 | The file inode-nr contains the first two items from | ||
105 | inode-state, so we'll skip to that file... | ||
106 | |||
107 | Inode-state contains three actual numbers and four dummies. | ||
108 | The actual numbers are, in order of appearance, nr_inodes, | ||
109 | nr_free_inodes and preshrink. | ||
110 | |||
111 | Nr_inodes stands for the number of inodes the system has | ||
112 | allocated, this can be slightly more than inode-max because | ||
113 | Linux allocates them one pageful at a time. | ||
114 | |||
115 | Nr_free_inodes represents the number of free inodes (?) and | ||
116 | preshrink is nonzero when the nr_inodes > inode-max and the | ||
117 | system needs to prune the inode list instead of allocating | ||
118 | more. | ||
119 | |||
120 | ============================================================== | ||
121 | |||
122 | overflowgid & overflowuid: | ||
123 | |||
124 | Some filesystems only support 16-bit UIDs and GIDs, although in Linux | ||
125 | UIDs and GIDs are 32 bits. When one of these filesystems is mounted | ||
126 | with writes enabled, any UID or GID that would exceed 65535 is translated | ||
127 | to a fixed value before being written to disk. | ||
128 | |||
129 | These sysctls allow you to change the value of the fixed UID and GID. | ||
130 | The default is 65534. | ||
131 | |||
132 | ============================================================== | ||
133 | |||
134 | super-max & super-nr: | ||
135 | |||
136 | These numbers control the maximum number of superblocks, and | ||
137 | thus the maximum number of mounted filesystems the kernel | ||
138 | can have. You only need to increase super-max if you need to | ||
139 | mount more filesystems than the current value in super-max | ||
140 | allows you to. | ||
141 | |||
142 | ============================================================== | ||
143 | |||
144 | aio-nr & aio-max-nr: | ||
145 | |||
146 | aio-nr shows the current system-wide number of asynchronous io | ||
147 | requests. aio-max-nr allows you to change the maximum value | ||
148 | aio-nr can grow to. | ||
149 | |||
150 | ============================================================== | ||
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt new file mode 100644 index 000000000000..35159176997b --- /dev/null +++ b/Documentation/sysctl/kernel.txt | |||
@@ -0,0 +1,314 @@ | |||
1 | Documentation for /proc/sys/kernel/* kernel version 2.2.10 | ||
2 | (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> | ||
3 | |||
4 | For general info and legal blurb, please look in README. | ||
5 | |||
6 | ============================================================== | ||
7 | |||
8 | This file contains documentation for the sysctl files in | ||
9 | /proc/sys/kernel/ and is valid for Linux kernel version 2.2. | ||
10 | |||
11 | The files in this directory can be used to tune and monitor | ||
12 | miscellaneous and general things in the operation of the Linux | ||
13 | kernel. Since some of the files _can_ be used to screw up your | ||
14 | system, it is advisable to read both documentation and source | ||
15 | before actually making adjustments. | ||
16 | |||
17 | Currently, these files might (depending on your configuration) | ||
18 | show up in /proc/sys/kernel: | ||
19 | - acct | ||
20 | - core_pattern | ||
21 | - core_uses_pid | ||
22 | - ctrl-alt-del | ||
23 | - dentry-state | ||
24 | - domainname | ||
25 | - hostname | ||
26 | - hotplug | ||
27 | - java-appletviewer [ binfmt_java, obsolete ] | ||
28 | - java-interpreter [ binfmt_java, obsolete ] | ||
29 | - l2cr [ PPC only ] | ||
30 | - modprobe ==> Documentation/kmod.txt | ||
31 | - msgmax | ||
32 | - msgmnb | ||
33 | - msgmni | ||
34 | - osrelease | ||
35 | - ostype | ||
36 | - overflowgid | ||
37 | - overflowuid | ||
38 | - panic | ||
39 | - pid_max | ||
40 | - powersave-nap [ PPC only ] | ||
41 | - printk | ||
42 | - real-root-dev ==> Documentation/initrd.txt | ||
43 | - reboot-cmd [ SPARC only ] | ||
44 | - rtsig-max | ||
45 | - rtsig-nr | ||
46 | - sem | ||
47 | - sg-big-buff [ generic SCSI device (sg) ] | ||
48 | - shmall | ||
49 | - shmmax [ sysv ipc ] | ||
50 | - shmmni | ||
51 | - stop-a [ SPARC only ] | ||
52 | - sysrq ==> Documentation/sysrq.txt | ||
53 | - tainted | ||
54 | - threads-max | ||
55 | - version | ||
56 | |||
57 | ============================================================== | ||
58 | |||
59 | acct: | ||
60 | |||
61 | highwater lowwater frequency | ||
62 | |||
63 | If BSD-style process accounting is enabled these values control | ||
64 | its behaviour. If free space on filesystem where the log lives | ||
65 | goes below <lowwater>% accounting suspends. If free space gets | ||
66 | above <highwater>% accounting resumes. <Frequency> determines | ||
67 | how often do we check the amount of free space (value is in | ||
68 | seconds). Default: | ||
69 | 4 2 30 | ||
70 | That is, suspend accounting if there left <= 2% free; resume it | ||
71 | if we got >=4%; consider information about amount of free space | ||
72 | valid for 30 seconds. | ||
73 | |||
74 | ============================================================== | ||
75 | |||
76 | core_pattern: | ||
77 | |||
78 | core_pattern is used to specify a core dumpfile pattern name. | ||
79 | . max length 64 characters; default value is "core" | ||
80 | . core_pattern is used as a pattern template for the output filename; | ||
81 | certain string patterns (beginning with '%') are substituted with | ||
82 | their actual values. | ||
83 | . backward compatibility with core_uses_pid: | ||
84 | If core_pattern does not include "%p" (default does not) | ||
85 | and core_uses_pid is set, then .PID will be appended to | ||
86 | the filename. | ||
87 | . corename format specifiers: | ||
88 | %<NUL> '%' is dropped | ||
89 | %% output one '%' | ||
90 | %p pid | ||
91 | %u uid | ||
92 | %g gid | ||
93 | %s signal number | ||
94 | %t UNIX time of dump | ||
95 | %h hostname | ||
96 | %e executable filename | ||
97 | %<OTHER> both are dropped | ||
98 | |||
99 | ============================================================== | ||
100 | |||
101 | core_uses_pid: | ||
102 | |||
103 | The default coredump filename is "core". By setting | ||
104 | core_uses_pid to 1, the coredump filename becomes core.PID. | ||
105 | If core_pattern does not include "%p" (default does not) | ||
106 | and core_uses_pid is set, then .PID will be appended to | ||
107 | the filename. | ||
108 | |||
109 | ============================================================== | ||
110 | |||
111 | ctrl-alt-del: | ||
112 | |||
113 | When the value in this file is 0, ctrl-alt-del is trapped and | ||
114 | sent to the init(1) program to handle a graceful restart. | ||
115 | When, however, the value is > 0, Linux's reaction to a Vulcan | ||
116 | Nerve Pinch (tm) will be an immediate reboot, without even | ||
117 | syncing its dirty buffers. | ||
118 | |||
119 | Note: when a program (like dosemu) has the keyboard in 'raw' | ||
120 | mode, the ctrl-alt-del is intercepted by the program before it | ||
121 | ever reaches the kernel tty layer, and it's up to the program | ||
122 | to decide what to do with it. | ||
123 | |||
124 | ============================================================== | ||
125 | |||
126 | domainname & hostname: | ||
127 | |||
128 | These files can be used to set the NIS/YP domainname and the | ||
129 | hostname of your box in exactly the same way as the commands | ||
130 | domainname and hostname, i.e.: | ||
131 | # echo "darkstar" > /proc/sys/kernel/hostname | ||
132 | # echo "mydomain" > /proc/sys/kernel/domainname | ||
133 | has the same effect as | ||
134 | # hostname "darkstar" | ||
135 | # domainname "mydomain" | ||
136 | |||
137 | Note, however, that the classic darkstar.frop.org has the | ||
138 | hostname "darkstar" and DNS (Internet Domain Name Server) | ||
139 | domainname "frop.org", not to be confused with the NIS (Network | ||
140 | Information Service) or YP (Yellow Pages) domainname. These two | ||
141 | domain names are in general different. For a detailed discussion | ||
142 | see the hostname(1) man page. | ||
143 | |||
144 | ============================================================== | ||
145 | |||
146 | hotplug: | ||
147 | |||
148 | Path for the hotplug policy agent. | ||
149 | Default value is "/sbin/hotplug". | ||
150 | |||
151 | ============================================================== | ||
152 | |||
153 | l2cr: (PPC only) | ||
154 | |||
155 | This flag controls the L2 cache of G3 processor boards. If | ||
156 | 0, the cache is disabled. Enabled if nonzero. | ||
157 | |||
158 | ============================================================== | ||
159 | |||
160 | osrelease, ostype & version: | ||
161 | |||
162 | # cat osrelease | ||
163 | 2.1.88 | ||
164 | # cat ostype | ||
165 | Linux | ||
166 | # cat version | ||
167 | #5 Wed Feb 25 21:49:24 MET 1998 | ||
168 | |||
169 | The files osrelease and ostype should be clear enough. Version | ||
170 | needs a little more clarification however. The '#5' means that | ||
171 | this is the fifth kernel built from this source base and the | ||
172 | date behind it indicates the time the kernel was built. | ||
173 | The only way to tune these values is to rebuild the kernel :-) | ||
174 | |||
175 | ============================================================== | ||
176 | |||
177 | overflowgid & overflowuid: | ||
178 | |||
179 | if your architecture did not always support 32-bit UIDs (i.e. arm, i386, | ||
180 | m68k, sh, and sparc32), a fixed UID and GID will be returned to | ||
181 | applications that use the old 16-bit UID/GID system calls, if the actual | ||
182 | UID or GID would exceed 65535. | ||
183 | |||
184 | These sysctls allow you to change the value of the fixed UID and GID. | ||
185 | The default is 65534. | ||
186 | |||
187 | ============================================================== | ||
188 | |||
189 | panic: | ||
190 | |||
191 | The value in this file represents the number of seconds the | ||
192 | kernel waits before rebooting on a panic. When you use the | ||
193 | software watchdog, the recommended setting is 60. | ||
194 | |||
195 | ============================================================== | ||
196 | |||
197 | panic_on_oops: | ||
198 | |||
199 | Controls the kernel's behaviour when an oops or BUG is encountered. | ||
200 | |||
201 | 0: try to continue operation | ||
202 | |||
203 | 1: delay a few seconds (to give klogd time to record the oops output) and | ||
204 | then panic. If the `panic' sysctl is also non-zero then the machine will | ||
205 | be rebooted. | ||
206 | |||
207 | ============================================================== | ||
208 | |||
209 | pid_max: | ||
210 | |||
211 | PID allocation wrap value. When the kenrel's next PID value | ||
212 | reaches this value, it wraps back to a minimum PID value. | ||
213 | PIDs of value pid_max or larger are not allocated. | ||
214 | |||
215 | ============================================================== | ||
216 | |||
217 | powersave-nap: (PPC only) | ||
218 | |||
219 | If set, Linux-PPC will use the 'nap' mode of powersaving, | ||
220 | otherwise the 'doze' mode will be used. | ||
221 | |||
222 | ============================================================== | ||
223 | |||
224 | printk: | ||
225 | |||
226 | The four values in printk denote: console_loglevel, | ||
227 | default_message_loglevel, minimum_console_loglevel and | ||
228 | default_console_loglevel respectively. | ||
229 | |||
230 | These values influence printk() behavior when printing or | ||
231 | logging error messages. See 'man 2 syslog' for more info on | ||
232 | the different loglevels. | ||
233 | |||
234 | - console_loglevel: messages with a higher priority than | ||
235 | this will be printed to the console | ||
236 | - default_message_level: messages without an explicit priority | ||
237 | will be printed with this priority | ||
238 | - minimum_console_loglevel: minimum (highest) value to which | ||
239 | console_loglevel can be set | ||
240 | - default_console_loglevel: default value for console_loglevel | ||
241 | |||
242 | ============================================================== | ||
243 | |||
244 | printk_ratelimit: | ||
245 | |||
246 | Some warning messages are rate limited. printk_ratelimit specifies | ||
247 | the minimum length of time between these messages (in jiffies), by | ||
248 | default we allow one every 5 seconds. | ||
249 | |||
250 | A value of 0 will disable rate limiting. | ||
251 | |||
252 | ============================================================== | ||
253 | |||
254 | printk_ratelimit_burst: | ||
255 | |||
256 | While long term we enforce one message per printk_ratelimit | ||
257 | seconds, we do allow a burst of messages to pass through. | ||
258 | printk_ratelimit_burst specifies the number of messages we can | ||
259 | send before ratelimiting kicks in. | ||
260 | |||
261 | ============================================================== | ||
262 | |||
263 | reboot-cmd: (Sparc only) | ||
264 | |||
265 | ??? This seems to be a way to give an argument to the Sparc | ||
266 | ROM/Flash boot loader. Maybe to tell it what to do after | ||
267 | rebooting. ??? | ||
268 | |||
269 | ============================================================== | ||
270 | |||
271 | rtsig-max & rtsig-nr: | ||
272 | |||
273 | The file rtsig-max can be used to tune the maximum number | ||
274 | of POSIX realtime (queued) signals that can be outstanding | ||
275 | in the system. | ||
276 | |||
277 | rtsig-nr shows the number of RT signals currently queued. | ||
278 | |||
279 | ============================================================== | ||
280 | |||
281 | sg-big-buff: | ||
282 | |||
283 | This file shows the size of the generic SCSI (sg) buffer. | ||
284 | You can't tune it just yet, but you could change it on | ||
285 | compile time by editing include/scsi/sg.h and changing | ||
286 | the value of SG_BIG_BUFF. | ||
287 | |||
288 | There shouldn't be any reason to change this value. If | ||
289 | you can come up with one, you probably know what you | ||
290 | are doing anyway :) | ||
291 | |||
292 | ============================================================== | ||
293 | |||
294 | shmmax: | ||
295 | |||
296 | This value can be used to query and set the run time limit | ||
297 | on the maximum shared memory segment size that can be created. | ||
298 | Shared memory segments up to 1Gb are now supported in the | ||
299 | kernel. This value defaults to SHMMAX. | ||
300 | |||
301 | ============================================================== | ||
302 | |||
303 | tainted: | ||
304 | |||
305 | Non-zero if the kernel has been tainted. Numeric values, which | ||
306 | can be ORed together: | ||
307 | |||
308 | 1 - A module with a non-GPL license has been loaded, this | ||
309 | includes modules with no license. | ||
310 | Set by modutils >= 2.4.9 and module-init-tools. | ||
311 | 2 - A module was force loaded by insmod -f. | ||
312 | Set by modutils >= 2.4.9 and module-init-tools. | ||
313 | 4 - Unsafe SMP processors: SMP with CPUs not designed for SMP. | ||
314 | |||
diff --git a/Documentation/sysctl/sunrpc.txt b/Documentation/sysctl/sunrpc.txt new file mode 100644 index 000000000000..ae1ecac6f85a --- /dev/null +++ b/Documentation/sysctl/sunrpc.txt | |||
@@ -0,0 +1,20 @@ | |||
1 | Documentation for /proc/sys/sunrpc/* kernel version 2.2.10 | ||
2 | (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> | ||
3 | |||
4 | For general info and legal blurb, please look in README. | ||
5 | |||
6 | ============================================================== | ||
7 | |||
8 | This file contains the documentation for the sysctl files in | ||
9 | /proc/sys/sunrpc and is valid for Linux kernel version 2.2. | ||
10 | |||
11 | The files in this directory can be used to (re)set the debug | ||
12 | flags of the SUN Remote Procedure Call (RPC) subsystem in | ||
13 | the Linux kernel. This stuff is used for NFS, KNFSD and | ||
14 | maybe a few other things as well. | ||
15 | |||
16 | The files in there are used to control the debugging flags: | ||
17 | rpc_debug, nfs_debug, nfsd_debug and nlm_debug. | ||
18 | |||
19 | These flags are for kernel hackers only. You should read the | ||
20 | source code in net/sunrpc/ for more information. | ||
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt new file mode 100644 index 000000000000..2f1aae32a5d9 --- /dev/null +++ b/Documentation/sysctl/vm.txt | |||
@@ -0,0 +1,104 @@ | |||
1 | Documentation for /proc/sys/vm/* kernel version 2.2.10 | ||
2 | (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> | ||
3 | |||
4 | For general info and legal blurb, please look in README. | ||
5 | |||
6 | ============================================================== | ||
7 | |||
8 | This file contains the documentation for the sysctl files in | ||
9 | /proc/sys/vm and is valid for Linux kernel version 2.2. | ||
10 | |||
11 | The files in this directory can be used to tune the operation | ||
12 | of the virtual memory (VM) subsystem of the Linux kernel and | ||
13 | the writeout of dirty data to disk. | ||
14 | |||
15 | Default values and initialization routines for most of these | ||
16 | files can be found in mm/swap.c. | ||
17 | |||
18 | Currently, these files are in /proc/sys/vm: | ||
19 | - overcommit_memory | ||
20 | - page-cluster | ||
21 | - dirty_ratio | ||
22 | - dirty_background_ratio | ||
23 | - dirty_expire_centisecs | ||
24 | - dirty_writeback_centisecs | ||
25 | - max_map_count | ||
26 | - min_free_kbytes | ||
27 | - laptop_mode | ||
28 | - block_dump | ||
29 | |||
30 | ============================================================== | ||
31 | |||
32 | dirty_ratio, dirty_background_ratio, dirty_expire_centisecs, | ||
33 | dirty_writeback_centisecs, vfs_cache_pressure, laptop_mode, | ||
34 | block_dump, swap_token_timeout: | ||
35 | |||
36 | See Documentation/filesystems/proc.txt | ||
37 | |||
38 | ============================================================== | ||
39 | |||
40 | overcommit_memory: | ||
41 | |||
42 | This value contains a flag that enables memory overcommitment. | ||
43 | |||
44 | When this flag is 0, the kernel attempts to estimate the amount | ||
45 | of free memory left when userspace requests more memory. | ||
46 | |||
47 | When this flag is 1, the kernel pretends there is always enough | ||
48 | memory until it actually runs out. | ||
49 | |||
50 | When this flag is 2, the kernel uses a "never overcommit" | ||
51 | policy that attempts to prevent any overcommit of memory. | ||
52 | |||
53 | This feature can be very useful because there are a lot of | ||
54 | programs that malloc() huge amounts of memory "just-in-case" | ||
55 | and don't use much of it. | ||
56 | |||
57 | The default value is 0. | ||
58 | |||
59 | See Documentation/vm/overcommit-accounting and | ||
60 | security/commoncap.c::cap_vm_enough_memory() for more information. | ||
61 | |||
62 | ============================================================== | ||
63 | |||
64 | overcommit_ratio: | ||
65 | |||
66 | When overcommit_memory is set to 2, the committed address | ||
67 | space is not permitted to exceed swap plus this percentage | ||
68 | of physical RAM. See above. | ||
69 | |||
70 | ============================================================== | ||
71 | |||
72 | page-cluster: | ||
73 | |||
74 | The Linux VM subsystem avoids excessive disk seeks by reading | ||
75 | multiple pages on a page fault. The number of pages it reads | ||
76 | is dependent on the amount of memory in your machine. | ||
77 | |||
78 | The number of pages the kernel reads in at once is equal to | ||
79 | 2 ^ page-cluster. Values above 2 ^ 5 don't make much sense | ||
80 | for swap because we only cluster swap data in 32-page groups. | ||
81 | |||
82 | ============================================================== | ||
83 | |||
84 | max_map_count: | ||
85 | |||
86 | This file contains the maximum number of memory map areas a process | ||
87 | may have. Memory map areas are used as a side-effect of calling | ||
88 | malloc, directly by mmap and mprotect, and also when loading shared | ||
89 | libraries. | ||
90 | |||
91 | While most applications need less than a thousand maps, certain | ||
92 | programs, particularly malloc debuggers, may consume lots of them, | ||
93 | e.g., up to one or two maps per allocation. | ||
94 | |||
95 | The default value is 65536. | ||
96 | |||
97 | ============================================================== | ||
98 | |||
99 | min_free_kbytes: | ||
100 | |||
101 | This is used to force the Linux VM to keep a minimum number | ||
102 | of kilobytes free. The VM uses this number to compute a pages_min | ||
103 | value for each lowmem zone in the system. Each lowmem zone gets | ||
104 | a number of reserved free pages based proportionally on its size. | ||