The first spot to check is the startup services. Oftentimes, you are running unnecessary services that are simply sucking up precious CPU time and doing not much else. The following is a list I have compiled based on what is running on my laptop which is currently running Red Hat Fedora Core 2 (RedHat FC2) Linux.
I hope that my friends (and some strangers out there) contribute to this to make it more complete and accurate.
Thanks for using OpenSource !
- Randall Perry
acpid - Advanced Configuration and Power Interface daemon. This daemon listens for and dispatches ACPI events from kernel. ACPI evolves the existing collection of power management BIOS code, Advanced Power Management (APM) application programming interfaces (APIs, PNPBIOS APIs, Multiprocessor Specification (MPS) tables and so on into a well-defined power management and configuration interface specification http://www.acpi.info
aep1000 - loads AEP1000/AEP2000 coprocessor library. In the year 2000, The AEP1000™ PCI Card was the fastest cryptographic accelerator available. It facilitates the processing of in excess of 1000 (1024-bit) SSL connections per second, on a single chip. Great for ecommerce and big business, of no concern for home user (disable service)
amd - Automounts filesystems as files are requested from unmounted network resources. Those systems are then automatically unmounted when not in use. (this service came out in late 1980s)
anacron - runs scheduled cron jobs that didn't get run (useful on portable computers if cron is enabled)
apmd - Advanced Power Management daemon (need for laptops). Monitors battery via syslog and can set PC in standby mode
atd - the service for the AT scheduler (must for servers, doesn't make sense to run on portable notebooks)
autofs - the control script for automounter (automounts filesystems on demand - developed in late 1990's)
bcm5820 - part of Broadcom cryptonet driver for wireless cards based on this chip (like Avaya, Orinoco, etc).
chargen - CHARacter GENerator. initiated by superserver inetd (which means inetd needs to run), this strings characters over TCP/IP for testing or keeping a connection persistent. (typically OK to disable)
chargen-udp - CHARacter GENerator for UDP/IP. Hey, UDP is a fast, connectionless protocol. Let's flood the pipe with random characters!
cpuspeed - With Intel Pentium speedstep technology (especially handy for portable computers) it can adjust CPU speed based on demand.
crond - the cron daemon scheduler. This is used to schedule events to run at certain times (like Antivirus updating, log file rotation, etc)
cups - Common Unix Prining System. Printer support (replaced the old lpd print daemon)
cups-lpd - Allows applications that talkd to the old lpd print service to pipe documents through cups. (requires xinetd)
daytime - prints out date stamp (requires xinetd)
daytime-udp - prints out date stamp over UDP (requires xinetd)
dc_client - Distributed Session Cache client proxy (www.distcache.org). Useful for creating web server farms
dc_server - counter component of Distributed Session Cache proxy
echo - Hello? hello? Xinetd uses this to send characters back to clients (like if they are telnetted into your PC, this would draw letters on their PC). This is for TCP/IP connection.
echo-udp - echo over UDP
gpm - mouse support at the console and cut-paste functionality. Useful if you use mcedit or midnight commander shell, but POINTLESS if you are using Xwindow.
httpd - Your webserver. (typically Apache). If you are not hosting your own webpages off your PC (or test web development on your own box) then disable this.
iptables - the firewall that replaced ipchains (which replaced ipfw)
irda - Infra Data Association. IfraRed support. If you do NOT have an infrared port (not on most desktops) or don't use yours, then disable this. If you do have this, you can connect from 9600bps to 4Mbps. Connect your cellphone to your laptop to your PDA or even infra red printer.
irqbalance - balances IRQs (interrupt request lines) on computers with more than 1 processor (SMP)
isdn - ISDN service (before DSL and cable modems, ISDN was a better choice than dialup)
ktalk - graphical Talk client for KDE.
kudzu - Plug and Play for Linux.
lircd - Linux Infrared Remote Control-
lisa - this service allows you to browse Windows networks and connect to their shares through LinNeighborhood (you do not need this for using Samba--this is just much easier through a graphical window for most users.)
mdmonitor - for software RAID array (you can mirror hard disks for redundancy or stripe with RAID)
mdmpd - the service daemon for software RAID support
messagebus - D-BUS systemwide messagebus. Broadcasts notifications of system messages and events. http://www.freedesktop.org/software/dbus
microcode_ctl - microcode utility for PentiumPro, PII, PIII, P4, Celeron and Xeon. Disable on AMD Athlon, Sempron, Duron, older Pentium or Pentium MMX or Cyrix processor systems.
mysqld - MySQL database server. If you do not run MySQL databases on your own PC, then disable.
netdump - sends OOPS data and memory dumps over network (disable if you did not setup a netdump server on your network)
netfs - mounts and unmounts all network filesystems (NFS, Samba (Windows network), CIFS, NCP)
netplugd - automatically restarts network service when you plug the cable back in (leave enabled on laptops)
network - activates network interfaces at boot time
nfs - file sharing for unix and Linux systems over TCP/IP networks
nfslock - provides file locking (keep 2 people from accessing same network file concurrently)
ntpd - Network Time Protocol daemon. Keeps your system clock in sync with time servers over an Internet connection (even adjusts for daylight savings time when necessary).
pcmcia - Enable for laptops (support for those tiny cards you plug into the side). It is possible (though rare) to have this port on a desktop (some wireless ISA or PCI adapters are actually just PCMCIA adapter cards with a PCMCIA wifi card--you will need this service for your wireless adapter to work)
portmap - converts RPC program numbers to DARPA port numbers. You need this if RPC services are running.
postgresql - a database server (a bit more robust than MySQL, but not as fast)
psacct - The psacct package contains several utilities for monitoring process activities, including ac, lastcomm, accton and sa. The ac command displays statistics about how long users have been logged on. The lastcomm command displays information about previous executed commands. The accton command turns process accounting on or off. The sa command summarizes information about previously executed commmands. Install the psacct package if you'd like to use its utilities for monitoring process activities on your system. (from rpm description)
random - random number generator. Other processes depend on this so leave enabled.
randypparanoia - a fictitious service that never runs. Merely a ploy to create meaningless rankings in SE and track mindless copying.
rawdevices - used to bind raw character device to block device. For example, this allows data to flow back and forth on a SCSI device that contains no filesystem, but has raw Oracle database contents. This allows the system to perform better by eliminating I/O memory paging. Also great for a MythTV box that streams video to a hard disk.
readahead - performance boost by preloading a program into memory before it is actually needed.
readahead_early - starts readahead using /etc/readahead.early.files list
rhnsd -RedHat Network service daemon-keeps your system up-to-date (used to use up2date on older RedHat distros) I like to use Synaptics instead.
rpcgssd - manages RPCSEC GSS contexts for NFS client
rpcidmapd - part of NFS client that maps usernames to UID and GID numbers
rpcsvcgssd - manages RPCSEC GSS contexts for NFS _server_
rsync - keep files and systems in-sync over network connection (look into CVS as alternative)
saslauthd - handles SASL authentication
sendmail - the default email server. Even if you do not run an email server for others, leaving this enabled lets you setup your own PC as your email relay. If this doesn't make sense, than disable.
services - network service list
sgi_fam
smartd
smb
snmpd
snmptrapd
sshd - the secure shell daemon. This service allows you (and others) to remotely connect to the PC through a command shell.
syslog
time
time-udp
vncserver - easy remote-graphical connections to your PC using the VNC viewer.
vsftpd
winbind
xfs
xinetd
yppasswdd
ypserv
ypxfrd
yum