KernelNewbies:

A glossary of various terms and acronyms related to the Linux kernel. If you know something, please create yourself an account (UserPreferences) and add a term in alphabetical order. Don't be afraid to improve other people's explanations, the goal is to have a high quality document for the readers of this site. If everybody who reads this page adds a term each week, this glossary should be complete within a few months...

Index

[#0-9 0-9]

[#A A]

[#B B]

[#C C]

[#D D]

[#E E]

[#F F]

[#G G]

[#H H]

[#I I]

[#J J]

[#K K]

[#L L]

[#M M]

[#N N]

[#O O]

[#P P]

[#Q Q]

[#R R]

[#S S]

[#T T]

[#U U]

[#V V]

[#W W]

[#X X]

[#Y Y]

[#Z Z]

Anchor(0-9)

0-9


2Q algorithm
MM algorithm based on two areas, one managed as a FIFO queue, and one as an LRU list.
8259 PIC
Outdated interrupt controller present on Intel hardware.

Anchor(A)

A


AIO

Asynchronous IO, IO that is performed without the issuing process blocking on IO completion.

Anticipatory Scheduler
A disk IO scheduler that leaves the disk idle after a read, in anticipation of the next read.

Anchor(B)

B


Anchor(C)

C


CBQ

Class Based Queueing, a hierarchical packet fair queueing qdisc. [http://www.icir.org/floyd/cbq.html CBQ Homepage]

Classifier
(also: filter or tcf) classifies a network packet by inspecting it, used by QDiscs.
Context switch
switching the CPU from running one thread to running another thread.
Copy-on-Write
(also: COW) reuse and share existing objects and copy them not until a modification is required.
Current
a kernel variable which points to the task_struct structure of the process currently running on this CPU.

Anchor(D)

D


Device Mapper
A technology for presenting arbitrary groupings of underlying sectors on physical devices in a consistent logical fashion usable by higher level algorithms. Heavily used by kernel technologies such as LVM.
Dwarf
Debugging Information Format

Anchor(E)

E


ELF

Executable Linkable Format, a popular binary format, the default for Linux on most architectures.

ematch
Extended Match, small classification helper attached to classifiers.

Anchor(F)

F


Anchor(G)

G


GRUB

GRand Unified Bootloader, a popular bootloader for Linux, BSD, and other OSes.

Anchor(H)

H


HTB

Hierachical Token Bucket, a qdisc based on TBF and CBQ. [http://luxik.cdi.cz/~devik/qos/htb/manual/theory.htm HTB Theory]

Anchor(I)

I


ISR

Interrupt Service Routine, the function in each device driver that gets called when an interrupt happens.

Anchor(J)

J


Jiffies
An incrementing counter representing system "uptime" in ticks - or the number of timer interrupts since boot. Ultimately the entire original concept of a jiffy will likely vanish as systems use timer events only when necessary and become "jiffyless".

Anchor(K)

K


kswapd
a kernel thread that frees up memory by evicting data from caches and paging out userspace memory, part of the virtual memory subsystem.

Anchor(L)

L


M

N

P

Q

R

S

T

U

V

X

Z

KernelNewbies: KernelGlossary (last edited 2006-04-16 06:45:26 by pool-68-160-189-26)