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authorJames Morris <jmorris@namei.org>2009-05-08 17:56:47 +1000
committerJames Morris <jmorris@namei.org>2009-05-08 17:56:47 +1000
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 a20a9066dc4..1286f455992 100644
--- a/Documentation/sysctl/00-INDEX
+++ b/Documentation/sysctl/00-INDEX
@@ -10,6 +10,8 @@ fs.txt
- documentation for /proc/sys/fs/*.
kernel.txt
- documentation for /proc/sys/kernel/*.
+net.txt
+ - documentation for /proc/sys/net/*.
sunrpc.txt
- documentation for /proc/sys/sunrpc/*.
vm.txt
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index f99254327ae..1458448436c 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -1,5 +1,6 @@
Documentation for /proc/sys/fs/* kernel version 2.2.10
(c) 1998, 1999, Rik van Riel <riel@nl.linux.org>
+ (c) 2009, Shen Feng<shen@cn.fujitsu.com>
For general info and legal blurb, please look in README.
@@ -14,7 +15,12 @@ kernel. Since some of the files _can_ be used to screw up your
system, it is advisable to read both documentation and source
before actually making adjustments.
+1. /proc/sys/fs
+----------------------------------------------------------
+
Currently, these files are in /proc/sys/fs:
+- aio-max-nr
+- aio-nr
- dentry-state
- dquot-max
- dquot-nr
@@ -30,8 +36,15 @@ Currently, these files are in /proc/sys/fs:
- super-max
- super-nr
-Documentation for the files in /proc/sys/fs/binfmt_misc is
-in Documentation/binfmt_misc.txt.
+==============================================================
+
+aio-nr & aio-max-nr:
+
+aio-nr is the running total of the number of events specified on the
+io_setup system call for all currently active aio contexts. If aio-nr
+reaches aio-max-nr then io_setup will fail with EAGAIN. Note that
+raising aio-max-nr does not result in the pre-allocation or re-sizing
+of any kernel data structures.
==============================================================
@@ -178,3 +191,60 @@ requests. aio-max-nr allows you to change the maximum value
aio-nr can grow to.
==============================================================
+
+
+2. /proc/sys/fs/binfmt_misc
+----------------------------------------------------------
+
+Documentation for the files in /proc/sys/fs/binfmt_misc is
+in Documentation/binfmt_misc.txt.
+
+
+3. /proc/sys/fs/mqueue - POSIX message queues filesystem
+----------------------------------------------------------
+
+The "mqueue" filesystem provides the necessary kernel features to enable the
+creation of a user space library that implements the POSIX message queues
+API (as noted by the MSG tag in the POSIX 1003.1-2001 version of the System
+Interfaces specification.)
+
+The "mqueue" filesystem contains values for determining/setting the amount of
+resources used by the file system.
+
+/proc/sys/fs/mqueue/queues_max is a read/write file for setting/getting the
+maximum number of message queues allowed on the system.
+
+/proc/sys/fs/mqueue/msg_max is a read/write file for setting/getting the
+maximum number of messages in a queue value. In fact it is the limiting value
+for another (user) limit which is set in mq_open invocation. This attribute of
+a queue must be less or equal then msg_max.
+
+/proc/sys/fs/mqueue/msgsize_max is a read/write file for setting/getting the
+maximum message size value (it is every message queue's attribute set during
+its creation).
+
+
+4. /proc/sys/fs/epoll - Configuration options for the epoll interface
+--------------------------------------------------------
+
+This directory contains configuration options for the epoll(7) interface.
+
+max_user_instances
+------------------
+
+This is the maximum number of epoll file descriptors that a single user can
+have open at a given time. The default value is 128, and should be enough
+for normal users.
+
+max_user_watches
+----------------
+
+Every epoll file descriptor can store a number of files to be monitored
+for event readiness. Each one of these monitored files constitutes a "watch".
+This configuration option sets the maximum number of "watches" that are
+allowed for each user.
+Each "watch" costs roughly 90 bytes on a 32bit kernel, and roughly 160 bytes
+on a 64bit one.
+The current default value for max_user_watches is the 1/32 of the available
+low memory, divided for the "watch" cost in bytes.
+
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 02b13495627..322a00bb99d 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -1,5 +1,6 @@
Documentation for /proc/sys/kernel/* kernel version 2.2.10
(c) 1998, 1999, Rik van Riel <riel@nl.linux.org>
+ (c) 2009, Shen Feng<shen@cn.fujitsu.com>
For general info and legal blurb, please look in README.
@@ -18,6 +19,7 @@ Currently, these files might (depending on your configuration)
show up in /proc/sys/kernel:
- acpi_video_flags
- acct
+- auto_msgmni
- core_pattern
- core_uses_pid
- ctrl-alt-del
@@ -34,6 +36,7 @@ show up in /proc/sys/kernel:
- msgmax
- msgmnb
- msgmni
+- nmi_watchdog
- osrelease
- ostype
- overflowgid
@@ -41,6 +44,7 @@ show up in /proc/sys/kernel:
- panic
- pid_max
- powersave-nap [ PPC only ]
+- panic_on_unrecovered_nmi
- printk
- randomize_va_space
- real-root-dev ==> Documentation/initrd.txt
@@ -56,6 +60,7 @@ show up in /proc/sys/kernel:
- sysrq ==> Documentation/sysrq.txt
- tainted
- threads-max
+- unknown_nmi_panic
- version
==============================================================
@@ -392,3 +397,51 @@ can be ORed together:
512 - A kernel warning has occurred.
1024 - A module from drivers/staging was loaded.
+==============================================================
+
+auto_msgmni:
+
+Enables/Disables automatic recomputing of msgmni upon memory add/remove or
+upon ipc namespace creation/removal (see the msgmni description above).
+Echoing "1" into this file enables msgmni automatic recomputing.
+Echoing "0" turns it off.
+auto_msgmni default value is 1.
+
+==============================================================
+
+nmi_watchdog:
+
+Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero
+the NMI watchdog is enabled and will continuously test all online cpus to
+determine whether or not they are still functioning properly. Currently,
+passing "nmi_watchdog=" parameter at boot time is required for this function
+to work.
+
+If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel parameter), the
+NMI watchdog shares registers with oprofile. By disabling the NMI watchdog,
+oprofile may have more registers to utilize.
+
+==============================================================
+
+unknown_nmi_panic:
+
+The value in this file affects behavior of handling NMI. When the value is
+non-zero, unknown NMI is trapped and then panic occurs. At that time, kernel
+debugging information is displayed on console.
+
+NMI switch that most IA32 servers have fires unknown NMI up, for example.
+If a system hangs up, try pressing the NMI switch.
+
+==============================================================
+
+panic_on_unrecovered_nmi:
+
+The default Linux behaviour on an NMI of either memory or unknown is to continue
+operation. For many environments such as scientific computing it is preferable
+that the box is taken out and the error dealt with than an uncorrected
+parity/ECC error get propogated.
+
+A small number of systems do generate NMI's for bizarre random reasons such as
+power management so the default is off. That sysctl works like the existing
+panic controls already in that directory.
+
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
new file mode 100644
index 00000000000..df38ef046f8
--- /dev/null
+++ b/Documentation/sysctl/net.txt
@@ -0,0 +1,175 @@
+Documentation for /proc/sys/net/* kernel version 2.4.0-test11-pre4
+ (c) 1999 Terrehon Bowden <terrehon@pacbell.net>
+ Bodo Bauer <bb@ricochet.net>
+ (c) 2000 Jorge Nerin <comandante@zaralinux.com>
+ (c) 2009 Shen Feng <shen@cn.fujitsu.com>
+
+For general info and legal blurb, please look in README.
+
+==============================================================
+
+This file contains the documentation for the sysctl files in
+/proc/sys/net and is valid for Linux kernel version 2.4.0-test11-pre4.
+
+The interface to the networking parts of the kernel is located in
+/proc/sys/net. The following table shows all possible subdirectories.You may
+see only some of them, depending on your kernel's configuration.
+
+
+Table : Subdirectories in /proc/sys/net
+..............................................................................
+ Directory Content Directory Content
+ core General parameter appletalk Appletalk protocol
+ unix Unix domain sockets netrom NET/ROM
+ 802 E802 protocol ax25 AX25
+ ethernet Ethernet protocol rose X.25 PLP layer
+ ipv4 IP version 4 x25 X.25 protocol
+ ipx IPX token-ring IBM token ring
+ bridge Bridging decnet DEC net
+ ipv6 IP version 6
+..............................................................................
+
+1. /proc/sys/net/core - Network core options
+-------------------------------------------------------
+
+rmem_default
+------------
+
+The default setting of the socket receive buffer in bytes.
+
+rmem_max
+--------
+
+The maximum receive socket buffer size in bytes.
+
+wmem_default
+------------
+
+The default setting (in bytes) of the socket send buffer.
+
+wmem_max
+--------
+
+The maximum send socket buffer size in bytes.
+
+message_burst and message_cost
+------------------------------
+
+These parameters are used to limit the warning messages written to the kernel
+log from the networking code. They enforce a rate limit to make a
+denial-of-service attack impossible. A higher message_cost factor, results in
+fewer messages that will be written. Message_burst controls when messages will
+be dropped. The default settings limit warning messages to one every five
+seconds.
+
+warnings
+--------
+
+This controls console messages from the networking stack that can occur because
+of problems on the network like duplicate address or bad checksums. Normally,
+this should be enabled, but if the problem persists the messages can be
+disabled.
+
+netdev_budget
+-------------
+
+Maximum number of packets taken from all interfaces in one polling cycle (NAPI
+poll). In one polling cycle interfaces which are registered to polling are
+probed in a round-robin manner. The limit of packets in one such probe can be
+set per-device via sysfs class/net/<device>/weight .
+
+netdev_max_backlog
+------------------
+
+Maximum number of packets, queued on the INPUT side, when the interface
+receives packets faster than kernel can process them.
+
+optmem_max
+----------
+
+Maximum ancillary buffer size allowed per socket. Ancillary data is a sequence
+of struct cmsghdr structures with appended data.
+
+2. /proc/sys/net/unix - Parameters for Unix domain sockets
+-------------------------------------------------------
+
+There is only one file in this directory.
+unix_dgram_qlen limits the max number of datagrams queued in Unix domain
+socket's buffer. It will not take effect unless PF_UNIX flag is specified.
+
+
+3. /proc/sys/net/ipv4 - IPV4 settings
+-------------------------------------------------------
+Please see: Documentation/networking/ip-sysctl.txt and ipvs-sysctl.txt for
+descriptions of these entries.
+
+
+4. Appletalk
+-------------------------------------------------------
+
+The /proc/sys/net/appletalk directory holds the Appletalk configuration data
+when Appletalk is loaded. The configurable parameters are:
+
+aarp-expiry-time
+----------------
+
+The amount of time we keep an ARP entry before expiring it. Used to age out
+old hosts.
+
+aarp-resolve-time
+-----------------
+
+The amount of time we will spend trying to resolve an Appletalk address.
+
+aarp-retransmit-limit
+---------------------
+
+The number of times we will retransmit a query before giving up.
+
+aarp-tick-time
+--------------
+
+Controls the rate at which expires are checked.
+
+The directory /proc/net/appletalk holds the list of active Appletalk sockets
+on a machine.
+
+The fields indicate the DDP type, the local address (in network:node format)
+the remote address, the size of the transmit pending queue, the size of the
+received queue (bytes waiting for applications to read) the state and the uid
+owning the socket.
+
+/proc/net/atalk_iface lists all the interfaces configured for appletalk.It
+shows the name of the interface, its Appletalk address, the network range on
+that address (or network number for phase 1 networks), and the status of the
+interface.
+
+/proc/net/atalk_route lists each known network route. It lists the target
+(network) that the route leads to, the router (may be directly connected), the
+route flags, and the device the route is using.
+
+
+5. IPX
+-------------------------------------------------------
+
+The IPX protocol has no tunable values in proc/sys/net.
+
+The IPX protocol does, however, provide proc/net/ipx. This lists each IPX
+socket giving the local and remote addresses in Novell format (that is
+network:node:port). In accordance with the strange Novell tradition,
+everything but the port is in hex. Not_Connected is displayed for sockets that
+are not tied to a specific remote address. The Tx and Rx queue sizes indicate
+the number of bytes pending for transmission and reception. The state
+indicates the state the socket is in and the uid is the owning uid of the
+socket.
+
+The /proc/net/ipx_interface file lists all IPX interfaces. For each interface
+it gives the network number, the node number, and indicates if the network is
+the primary network. It also indicates which device it is bound to (or
+Internal for internal networks) and the Frame Type if appropriate. Linux
+supports 802.3, 802.2, 802.2 SNAP and DIX (Blue Book) ethernet framing for
+IPX.
+
+The /proc/net/ipx_route table holds a list of IPX routes. For each route it
+gives the destination network, the router node (or Directly) and the network
+address of the router (or Connected) for internal networks.
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 3197fc83bc5..b716d33912d 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -39,6 +39,8 @@ Currently, these files are in /proc/sys/vm:
- nr_hugepages
- nr_overcommit_hugepages
- nr_pdflush_threads
+- nr_pdflush_threads_min
+- nr_pdflush_threads_max
- nr_trim_pages (only if CONFIG_MMU=n)
- numa_zonelist_order
- oom_dump_tasks
@@ -88,6 +90,10 @@ will itself start writeback.
If dirty_bytes is written, dirty_ratio becomes a function of its value
(dirty_bytes / the amount of dirtyable system memory).
+Note: the minimum value allowed for dirty_bytes is two pages (in bytes); any
+value lower than this limit will be ignored and the old configuration will be
+retained.
+
==============================================================
dirty_expire_centisecs
@@ -463,6 +469,32 @@ The default value is 0.
==============================================================
+nr_pdflush_threads_min
+
+This value controls the minimum number of pdflush threads.
+
+At boot time, the kernel will create and maintain 'nr_pdflush_threads_min'
+threads for the kernel's lifetime.
+
+The default value is 2. The minimum value you can specify is 1, and
+the maximum value is the current setting of 'nr_pdflush_threads_max'.
+
+See 'nr_pdflush_threads_max' below for more information.
+
+==============================================================
+
+nr_pdflush_threads_max
+
+This value controls the maximum number of pdflush threads that can be
+created. The pdflush algorithm will create a new pdflush thread (up to
+this maximum) if no pdflush threads have been available for >= 1 second.
+
+The default value is 8. The minimum value you can specify is the
+current value of 'nr_pdflush_threads_min' and the
+maximum is 1000.
+
+==============================================================
+
overcommit_memory:
This value contains a flag that enables memory overcommitment.