Proc/Command - Red Hat ENTERPRISE LINUX 3 Reference Manual

76
— Sets the number of pages read in a single attempt. The default value of
• page-cluster
actually relates to 16 pages, is appropriate for most systems.
• pagetable_cache
The first and second values relate to the minimum and maximum number of page tables to set aside,
respectively.
The
/usr/src/linux-2.4/Documentation/sysctl/vm.txt
tion on these files.
5.3.10.
/proc/sysvipc/
This directory contains information about System V IPC resources. The files in this directory relate to
System V IPC calls for messages (
5.3.11.
/proc/tty/
This directory contains information about the available and currently used tty devices on the system.
Originally called teletype devices, any character-based data terminals are called tty devices.
In Linux, there are three different kinds of tty devices. Serial devices are used with serial connections,
such as over a modem or using a serial cable. Virtual terminals create the common console connection,
such as the virtual consoles available when pressing [Alt]-[ F-key ] at the system console. Pseudo
terminals create a two-way communication that is used by some higher level applications, such as
XFree86. The
drivers
serial
serial
pty_slave
pty_master
pty_slave
pty_master
/dev/vc/0
/dev/ptmx
/dev/console
/dev/tty
unknown
The
/proc/tty/driver/serial
lines.
In order for tty devices to be used as network devices, the Linux kernel enforces line discipline on the
device. This allows the driver to place a specific type of header with every block of data transmitted
over the device, making it possible for the remote end of the connection to a block of data as just one
in a stream of data blocks. SLIP and PPP are common line disciplines, and each are commonly used
to connect systems to one other over a serial link.
Registered line disciplines are stored in the
within the directory.
ldisc/
5.4. Using the
sysctl
The
/sbin/sysctl
directory.
— Controls the number of page tables that are cached on a per-processor basis.
), semaphores (
msg
file is a list of the current tty devices in use, as in the following example:
/dev/cua
/dev/ttyS
/dev/pts
/dev/ptm
/dev/ttyp
/dev/pty
/dev/vc/0
/dev/ptmx
/dev/console
/dev/tty
/dev/vc/%d
file lists the usage statistics and status of each of the serial tty
Command
command is used to view, set, and automate kernel settings in the
Chapter 5. The
), and shared memory (
sem
5 64-127 serial:callout
4 64-127 serial
136 0-255 pty:slave
128 0-255 pty:master
3 0-255 pty:slave
2 0-255 pty:master
4 0 system:vtmaster
5 2 system
5 1 system:console
5 0 system:/dev/tty
4 1-63 console
file, and more detailed information is available
ldiscs
proc
file contains additional informa-
).
shm
/proc/sys/
File System
, which
3