Red Hat ENTERPRISE LINUX 3 Reference Manual page 87

proc
Chapter 5. The
5.3.9.1.
/proc/sys/dev/
This directory provides parameters for particular devices on the system. Most systems have at least
two directories,
cdrom
which provides the ability to share one parallel port between multiple device drivers.
The directory contains a file called
cdrom
parameters:
CD-ROM information, Id: cdrom.c 3.12 2000/10/18
drive name: hdc
drive speed: 32
drive # of slots: 1
Can close tray:
Can open tray:
Can lock tray:
Can change speed: 1
Can select disk: 0
Can read multisession: 1
Can read MCN: 1
Reports media changed: 1
Can play audio:
Can write CD-R:
Can write CD-RW: 0
Can read DVD: 0
Can write DVD-R: 0
Can write DVD-RAM: 0
This file can be quickly scanned to discover the qualities of an unknown CD-ROM. If multiple CD-
ROMs are available on a system, each device is given its own column of information.
Various files in
/proc/sys/dev/cdrom
trol the system's CD-ROM. Use the
If RAID support is compiled into the kernel, a
with at least two files in it:
the acceleration of RAID devices for I/O intensive tasks, such as resyncing the disks.
5.3.9.2.
/proc/sys/fs/
This directory contains an array of options and information concerning various aspects of the file
system, including quota, file handle, inode, and dentry information.
The directory is used to provide kernel support for miscellaneous binary formats.
binfmt_misc
The important files in
— Provides the status of the directory cache. The file looks similar to the follow-
• dentry-state
ing:
57411 52939 45 0 0 0
The first number reveals the total number of directory cache entries, while the second number
displays the number of unused entries. The third number tells the number of seconds between when
a directory has been freed and when it can be reclaimed, and the fourth measures the pages currently
requested by the system. The last two numbers are not used and display only zeros.
— Lists the maximum number of cached disk quota entries.
• dquot-nr
— Lists the maximum number of file handles that the kernel will allocate. Raising the
• file-max
value in this file can resolve errors caused by a lack of available file handles.
File System
and . Customized kernels can have other directories, such as
raid
1
1
1
1
0
, such as
echo
speed_limit_min
include:
/proc/sys/fs
, which reveals a number of important CD-ROM
info
and
autoclose
command to enable or disable these features.
/proc/sys/dev/raid/
and
speed_limit_max
, can be used to con-
checkmedia
directory becomes available
. These settings determine
69
,
parport