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authorJames Morris <jmorris@namei.org>2009-05-08 03:56:47 -0400
committerJames Morris <jmorris@namei.org>2009-05-08 03:56:47 -0400
commitd254117099d711f215e62427f55dfb8ebd5ad011 (patch)
tree0848ff8dd74314fec14a86497f8d288c86ba7c65 /Documentation/sysctl
parent07ff7a0b187f3951788f64ae1f30e8109bc8e9eb (diff)
parent8c9ed899b44c19e81859fbb0e9d659fe2f8630fc (diff)
Merge branch 'master' into next
Diffstat (limited to 'Documentation/sysctl')
-rw-r--r--Documentation/sysctl/00-INDEX2
-rw-r--r--Documentation/sysctl/fs.txt74
-rw-r--r--Documentation/sysctl/kernel.txt53
-rw-r--r--Documentation/sysctl/net.txt175
-rw-r--r--Documentation/sysctl/vm.txt32
5 files changed, 334 insertions, 2 deletions
diff --git a/Documentation/sysctl/00-INDEX b/Documentation/sysctl/00-INDEX
index a20a9066dc4c..1286f455992f 100644
--- a/Documentation/sysctl/00-INDEX
+++ b/Documentation/sysctl/00-INDEX
@@ -10,6 +10,8 @@ fs.txt
10 - documentation for /proc/sys/fs/*. 10 - documentation for /proc/sys/fs/*.
11kernel.txt 11kernel.txt
12 - documentation for /proc/sys/kernel/*. 12 - documentation for /proc/sys/kernel/*.
13net.txt
14 - documentation for /proc/sys/net/*.
13sunrpc.txt 15sunrpc.txt
14 - documentation for /proc/sys/sunrpc/*. 16 - documentation for /proc/sys/sunrpc/*.
15vm.txt 17vm.txt
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index f99254327ae5..1458448436cc 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -1,5 +1,6 @@
1Documentation for /proc/sys/fs/* kernel version 2.2.10 1Documentation for /proc/sys/fs/* kernel version 2.2.10
2 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> 2 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org>
3 (c) 2009, Shen Feng<shen@cn.fujitsu.com>
3 4
4For general info and legal blurb, please look in README. 5For general info and legal blurb, please look in README.
5 6
@@ -14,7 +15,12 @@ kernel. Since some of the files _can_ be used to screw up your
14system, it is advisable to read both documentation and source 15system, it is advisable to read both documentation and source
15before actually making adjustments. 16before actually making adjustments.
16 17
181. /proc/sys/fs
19----------------------------------------------------------
20
17Currently, these files are in /proc/sys/fs: 21Currently, these files are in /proc/sys/fs:
22- aio-max-nr
23- aio-nr
18- dentry-state 24- dentry-state
19- dquot-max 25- dquot-max
20- dquot-nr 26- dquot-nr
@@ -30,8 +36,15 @@ Currently, these files are in /proc/sys/fs:
30- super-max 36- super-max
31- super-nr 37- super-nr
32 38
33Documentation for the files in /proc/sys/fs/binfmt_misc is 39==============================================================
34in Documentation/binfmt_misc.txt. 40
41aio-nr & aio-max-nr:
42
43aio-nr is the running total of the number of events specified on the
44io_setup system call for all currently active aio contexts. If aio-nr
45reaches aio-max-nr then io_setup will fail with EAGAIN. Note that
46raising aio-max-nr does not result in the pre-allocation or re-sizing
47of any kernel data structures.
35 48
36============================================================== 49==============================================================
37 50
@@ -178,3 +191,60 @@ requests. aio-max-nr allows you to change the maximum value
178aio-nr can grow to. 191aio-nr can grow to.
179 192
180============================================================== 193==============================================================
194
195
1962. /proc/sys/fs/binfmt_misc
197----------------------------------------------------------
198
199Documentation for the files in /proc/sys/fs/binfmt_misc is
200in Documentation/binfmt_misc.txt.
201
202
2033. /proc/sys/fs/mqueue - POSIX message queues filesystem
204----------------------------------------------------------
205
206The "mqueue" filesystem provides the necessary kernel features to enable the
207creation of a user space library that implements the POSIX message queues
208API (as noted by the MSG tag in the POSIX 1003.1-2001 version of the System
209Interfaces specification.)
210
211The "mqueue" filesystem contains values for determining/setting the amount of
212resources used by the file system.
213
214/proc/sys/fs/mqueue/queues_max is a read/write file for setting/getting the
215maximum number of message queues allowed on the system.
216
217/proc/sys/fs/mqueue/msg_max is a read/write file for setting/getting the
218maximum number of messages in a queue value. In fact it is the limiting value
219for another (user) limit which is set in mq_open invocation. This attribute of
220a queue must be less or equal then msg_max.
221
222/proc/sys/fs/mqueue/msgsize_max is a read/write file for setting/getting the
223maximum message size value (it is every message queue's attribute set during
224its creation).
225
226
2274. /proc/sys/fs/epoll - Configuration options for the epoll interface
228--------------------------------------------------------
229
230This directory contains configuration options for the epoll(7) interface.
231
232max_user_instances
233------------------
234
235This is the maximum number of epoll file descriptors that a single user can
236have open at a given time. The default value is 128, and should be enough
237for normal users.
238
239max_user_watches
240----------------
241
242Every epoll file descriptor can store a number of files to be monitored
243for event readiness. Each one of these monitored files constitutes a "watch".
244This configuration option sets the maximum number of "watches" that are
245allowed for each user.
246Each "watch" costs roughly 90 bytes on a 32bit kernel, and roughly 160 bytes
247on a 64bit one.
248The current default value for max_user_watches is the 1/32 of the available
249low memory, divided for the "watch" cost in bytes.
250
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 02b134956273..322a00bb99d9 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -1,5 +1,6 @@
1Documentation for /proc/sys/kernel/* kernel version 2.2.10 1Documentation for /proc/sys/kernel/* kernel version 2.2.10
2 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> 2 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org>
3 (c) 2009, Shen Feng<shen@cn.fujitsu.com>
3 4
4For general info and legal blurb, please look in README. 5For general info and legal blurb, please look in README.
5 6
@@ -18,6 +19,7 @@ Currently, these files might (depending on your configuration)
18show up in /proc/sys/kernel: 19show up in /proc/sys/kernel:
19- acpi_video_flags 20- acpi_video_flags
20- acct 21- acct
22- auto_msgmni
21- core_pattern 23- core_pattern
22- core_uses_pid 24- core_uses_pid
23- ctrl-alt-del 25- ctrl-alt-del
@@ -34,6 +36,7 @@ show up in /proc/sys/kernel:
34- msgmax 36- msgmax
35- msgmnb 37- msgmnb
36- msgmni 38- msgmni
39- nmi_watchdog
37- osrelease 40- osrelease
38- ostype 41- ostype
39- overflowgid 42- overflowgid
@@ -41,6 +44,7 @@ show up in /proc/sys/kernel:
41- panic 44- panic
42- pid_max 45- pid_max
43- powersave-nap [ PPC only ] 46- powersave-nap [ PPC only ]
47- panic_on_unrecovered_nmi
44- printk 48- printk
45- randomize_va_space 49- randomize_va_space
46- real-root-dev ==> Documentation/initrd.txt 50- real-root-dev ==> Documentation/initrd.txt
@@ -56,6 +60,7 @@ show up in /proc/sys/kernel:
56- sysrq ==> Documentation/sysrq.txt 60- sysrq ==> Documentation/sysrq.txt
57- tainted 61- tainted
58- threads-max 62- threads-max
63- unknown_nmi_panic
59- version 64- version
60 65
61============================================================== 66==============================================================
@@ -392,3 +397,51 @@ can be ORed together:
392 512 - A kernel warning has occurred. 397 512 - A kernel warning has occurred.
3931024 - A module from drivers/staging was loaded. 3981024 - A module from drivers/staging was loaded.
394 399
400==============================================================
401
402auto_msgmni:
403
404Enables/Disables automatic recomputing of msgmni upon memory add/remove or
405upon ipc namespace creation/removal (see the msgmni description above).
406Echoing "1" into this file enables msgmni automatic recomputing.
407Echoing "0" turns it off.
408auto_msgmni default value is 1.
409
410==============================================================
411
412nmi_watchdog:
413
414Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero
415the NMI watchdog is enabled and will continuously test all online cpus to
416determine whether or not they are still functioning properly. Currently,
417passing "nmi_watchdog=" parameter at boot time is required for this function
418to work.
419
420If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel parameter), the
421NMI watchdog shares registers with oprofile. By disabling the NMI watchdog,
422oprofile may have more registers to utilize.
423
424==============================================================
425
426unknown_nmi_panic:
427
428The value in this file affects behavior of handling NMI. When the value is
429non-zero, unknown NMI is trapped and then panic occurs. At that time, kernel
430debugging information is displayed on console.
431
432NMI switch that most IA32 servers have fires unknown NMI up, for example.
433If a system hangs up, try pressing the NMI switch.
434
435==============================================================
436
437panic_on_unrecovered_nmi:
438
439The default Linux behaviour on an NMI of either memory or unknown is to continue
440operation. For many environments such as scientific computing it is preferable
441that the box is taken out and the error dealt with than an uncorrected
442parity/ECC error get propogated.
443
444A small number of systems do generate NMI's for bizarre random reasons such as
445power management so the default is off. That sysctl works like the existing
446panic controls already in that directory.
447
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
new file mode 100644
index 000000000000..df38ef046f8d
--- /dev/null
+++ b/Documentation/sysctl/net.txt
@@ -0,0 +1,175 @@
1Documentation for /proc/sys/net/* kernel version 2.4.0-test11-pre4
2 (c) 1999 Terrehon Bowden <terrehon@pacbell.net>
3 Bodo Bauer <bb@ricochet.net>
4 (c) 2000 Jorge Nerin <comandante@zaralinux.com>
5 (c) 2009 Shen Feng <shen@cn.fujitsu.com>
6
7For general info and legal blurb, please look in README.
8
9==============================================================
10
11This file contains the documentation for the sysctl files in
12/proc/sys/net and is valid for Linux kernel version 2.4.0-test11-pre4.
13
14The interface to the networking parts of the kernel is located in
15/proc/sys/net. The following table shows all possible subdirectories.You may
16see only some of them, depending on your kernel's configuration.
17
18
19Table : Subdirectories in /proc/sys/net
20..............................................................................
21 Directory Content Directory Content
22 core General parameter appletalk Appletalk protocol
23 unix Unix domain sockets netrom NET/ROM
24 802 E802 protocol ax25 AX25
25 ethernet Ethernet protocol rose X.25 PLP layer
26 ipv4 IP version 4 x25 X.25 protocol
27 ipx IPX token-ring IBM token ring
28 bridge Bridging decnet DEC net
29 ipv6 IP version 6
30..............................................................................
31
321. /proc/sys/net/core - Network core options
33-------------------------------------------------------
34
35rmem_default
36------------
37
38The default setting of the socket receive buffer in bytes.
39
40rmem_max
41--------
42
43The maximum receive socket buffer size in bytes.
44
45wmem_default
46------------
47
48The default setting (in bytes) of the socket send buffer.
49
50wmem_max
51--------
52
53The maximum send socket buffer size in bytes.
54
55message_burst and message_cost
56------------------------------
57
58These parameters are used to limit the warning messages written to the kernel
59log from the networking code. They enforce a rate limit to make a
60denial-of-service attack impossible. A higher message_cost factor, results in
61fewer messages that will be written. Message_burst controls when messages will
62be dropped. The default settings limit warning messages to one every five
63seconds.
64
65warnings
66--------
67
68This controls console messages from the networking stack that can occur because
69of problems on the network like duplicate address or bad checksums. Normally,
70this should be enabled, but if the problem persists the messages can be
71disabled.
72
73netdev_budget
74-------------
75
76Maximum number of packets taken from all interfaces in one polling cycle (NAPI
77poll). In one polling cycle interfaces which are registered to polling are
78probed in a round-robin manner. The limit of packets in one such probe can be
79set per-device via sysfs class/net/<device>/weight .
80
81netdev_max_backlog
82------------------
83
84Maximum number of packets, queued on the INPUT side, when the interface
85receives packets faster than kernel can process them.
86
87optmem_max
88----------
89
90Maximum ancillary buffer size allowed per socket. Ancillary data is a sequence
91of struct cmsghdr structures with appended data.
92
932. /proc/sys/net/unix - Parameters for Unix domain sockets
94-------------------------------------------------------
95
96There is only one file in this directory.
97unix_dgram_qlen limits the max number of datagrams queued in Unix domain
98socket's buffer. It will not take effect unless PF_UNIX flag is specified.
99
100
1013. /proc/sys/net/ipv4 - IPV4 settings
102-------------------------------------------------------
103Please see: Documentation/networking/ip-sysctl.txt and ipvs-sysctl.txt for
104descriptions of these entries.
105
106
1074. Appletalk
108-------------------------------------------------------
109
110The /proc/sys/net/appletalk directory holds the Appletalk configuration data
111when Appletalk is loaded. The configurable parameters are:
112
113aarp-expiry-time
114----------------
115
116The amount of time we keep an ARP entry before expiring it. Used to age out
117old hosts.
118
119aarp-resolve-time
120-----------------
121
122The amount of time we will spend trying to resolve an Appletalk address.
123
124aarp-retransmit-limit
125---------------------
126
127The number of times we will retransmit a query before giving up.
128
129aarp-tick-time
130--------------
131
132Controls the rate at which expires are checked.
133
134The directory /proc/net/appletalk holds the list of active Appletalk sockets
135on a machine.
136
137The fields indicate the DDP type, the local address (in network:node format)
138the remote address, the size of the transmit pending queue, the size of the
139received queue (bytes waiting for applications to read) the state and the uid
140owning the socket.
141
142/proc/net/atalk_iface lists all the interfaces configured for appletalk.It
143shows the name of the interface, its Appletalk address, the network range on
144that address (or network number for phase 1 networks), and the status of the
145interface.
146
147/proc/net/atalk_route lists each known network route. It lists the target
148(network) that the route leads to, the router (may be directly connected), the
149route flags, and the device the route is using.
150
151
1525. IPX
153-------------------------------------------------------
154
155The IPX protocol has no tunable values in proc/sys/net.
156
157The IPX protocol does, however, provide proc/net/ipx. This lists each IPX
158socket giving the local and remote addresses in Novell format (that is
159network:node:port). In accordance with the strange Novell tradition,
160everything but the port is in hex. Not_Connected is displayed for sockets that
161are not tied to a specific remote address. The Tx and Rx queue sizes indicate
162the number of bytes pending for transmission and reception. The state
163indicates the state the socket is in and the uid is the owning uid of the
164socket.
165
166The /proc/net/ipx_interface file lists all IPX interfaces. For each interface
167it gives the network number, the node number, and indicates if the network is
168the primary network. It also indicates which device it is bound to (or
169Internal for internal networks) and the Frame Type if appropriate. Linux
170supports 802.3, 802.2, 802.2 SNAP and DIX (Blue Book) ethernet framing for
171IPX.
172
173The /proc/net/ipx_route table holds a list of IPX routes. For each route it
174gives the destination network, the router node (or Directly) and the network
175address of the router (or Connected) for internal networks.
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 3197fc83bc51..b716d33912d8 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -39,6 +39,8 @@ Currently, these files are in /proc/sys/vm:
39- nr_hugepages 39- nr_hugepages
40- nr_overcommit_hugepages 40- nr_overcommit_hugepages
41- nr_pdflush_threads 41- nr_pdflush_threads
42- nr_pdflush_threads_min
43- nr_pdflush_threads_max
42- nr_trim_pages (only if CONFIG_MMU=n) 44- nr_trim_pages (only if CONFIG_MMU=n)
43- numa_zonelist_order 45- numa_zonelist_order
44- oom_dump_tasks 46- oom_dump_tasks
@@ -88,6 +90,10 @@ will itself start writeback.
88If dirty_bytes is written, dirty_ratio becomes a function of its value 90If dirty_bytes is written, dirty_ratio becomes a function of its value
89(dirty_bytes / the amount of dirtyable system memory). 91(dirty_bytes / the amount of dirtyable system memory).
90 92
93Note: the minimum value allowed for dirty_bytes is two pages (in bytes); any
94value lower than this limit will be ignored and the old configuration will be
95retained.
96
91============================================================== 97==============================================================
92 98
93dirty_expire_centisecs 99dirty_expire_centisecs
@@ -463,6 +469,32 @@ The default value is 0.
463 469
464============================================================== 470==============================================================
465 471
472nr_pdflush_threads_min
473
474This value controls the minimum number of pdflush threads.
475
476At boot time, the kernel will create and maintain 'nr_pdflush_threads_min'
477threads for the kernel's lifetime.
478
479The default value is 2. The minimum value you can specify is 1, and
480the maximum value is the current setting of 'nr_pdflush_threads_max'.
481
482See 'nr_pdflush_threads_max' below for more information.
483
484==============================================================
485
486nr_pdflush_threads_max
487
488This value controls the maximum number of pdflush threads that can be
489created. The pdflush algorithm will create a new pdflush thread (up to
490this maximum) if no pdflush threads have been available for >= 1 second.
491
492The default value is 8. The minimum value you can specify is the
493current value of 'nr_pdflush_threads_min' and the
494maximum is 1000.
495
496==============================================================
497
466overcommit_memory: 498overcommit_memory:
467 499
468This value contains a flag that enables memory overcommitment. 500This value contains a flag that enables memory overcommitment.