Linux performance tips

These were done on RedHat Fedora.

• Turn off unneeded services/daemons.
  Use 'ntsysv' or the gnome desktop Main menu->System Settings->Server Settings->Services to deselect services. The services you need:
  • anacron (runs scheduled jobs)
  • iptables (only if you want a personal firewall)
  • network (only if you want to connect to a network)
  • pcmcia (only if you use the PC card slot)
  • random (it's recommended but maybe unnecessary). Update: gone from Fedora 3.
  • syslog (for logging, I don't know if it's required). messagebus also needed.
  • cpuspeed (to slow down CPU on laptop).
  • readahead (pre-loads config files)
  • acpid (for power management, laptops only? really needed?)
  • xfs (X won't start without it)
  ntsysv doesn't kill running services, it's selections take effect the next boot. The gnome Service Configuration can also terminate running services. KDE has a similar app.
  Manually deselecting services: delete the Snnservice file in /etc/rc.d/rc5.d/
  Manually stopping service process:
  /etc/rc.d/init.d/service_name stop
• Run scheduled tasks less frequently.
  cron/anacron runs scheduled jobs based on files in /etc/cron.daily/. The worst is the slocate.cron file which builds a database of all files and typically starts soon after you've booted and ties up the disk for many minutes. This doesn't need daily running on a personal system; move the file to the cron.weekly or even cron.monthly directory:
  mv /etc/cron.daily/slocate.cron /etc/cron.weekly/
• Let the prelink scheduled job run. prelink does some manipulation with the shared libraries so they load faster, thus programs start faster.
• Reduce the number of mingetty terminals from 6 to 1 or 0.
  mingetty is a virtual text-mode terminal. Accessible by ctrl-alt-f1 etc. (ctrl-alt-f7 is the X terminal). Not needed and unlikely to be used.
  To see their running processes:
  ps aux | grep mingetty
  will show six of them running (corresponding to ctrl-alt f1-f6). If they're killed they come back. Need to edit /etc/inittab and put a # in front of lines
  1:2345:respawn:/sbin/mingetty tty1
  Takes effect next boot.
• Install more RAM.
• Don't run a bloated desktop like gnome or kde.
  Try the fvwm2 window manager instead. It will have to downloaded (1.2MB RPM file plus the 9KB libstroke RPM) from fvwm.org, installed (rpm -i fvwm.....), and configured into the login setup. (I can't figure out how to use it with gdm so this setup uses kdm.)
  1. Edit /etc/X11/xdm/Xsession to add this as another choice in the case statement after line 108:

         fvwm)
            exec -l $SHELL -c "$SSHAGENT /usr/share/apps/switchdesk/Xclients.fvwm"
           ;;
     

     (Notice it's similar to the surrounding choices.)
  2. Add a line to /etc/sysconfig/desktop
     DISPLAYMANAGER="KDE"
  3. Edit the /usr/share/apps/switchdesk/Xclient.fvwm file so that the pathname in it is: /usr/bin/fvwm2 (i.e. remove the X11R6 component).
  4. Kill the running gdm process. Or reboot.

  fvwm can be configured to look better...

  Fedora 3 provides xfce window manager instead. Version 4 is better than the provided version 3 (menus, hotkeys can replace mousing, and can run xplanet on desktop).

• Triage on extremely under-powered system: don't run X, run in text-mode only.
  'telinit 3' will switch to runlevel 3 which is text-mode. Runlevel 5 is the default X-based mode. The line in /etc/inittab that looks like:
  id:5:initdefault:
  controls which runlevel the system boots up in. Change the 5 to a 3 so subsequent boots are in runlevel 3 (text-mode only).

  Can do anything non-graphical.

• Recompile the kernel so it's lean and mean, tailored to your system's hardware and applications. I don't know how much performance this adds.