10-18-2008
I really have to agree with cfajohnson. Putting sed in a loop where you process, say, 50,000 records means that your script must fork() and exec() 50,000 times. And that's assuming that you limited yourself to a single invocation of sed. If you used 10 sed's per record, now you need 500,000 forks() and exec() pairs. That is one million very expensive system calls added to a script. And it doesn't need to be 10 sed's... 10 invocations of stuff like cut, sed, awk, tr, basename, dirname, cat, etc will do the trick.
It is not unusual to see scripts that invoke 10 or more external programs like sed in an inner loop like that. When I am asked to speed up a slow script, this is the first thing I look for. It usually takes me about 10 minutes to rewrite the script in a way that saves millions and millions of system calls.
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LEARN ABOUT CENTOS
plymouth-set-default-theme
PLYMOUTH-SET-DEFAU(1) User Commands PLYMOUTH-SET-DEFAU(1)
NAME
plymouth-set-default-theme - Set the plymouth theme
SYNOPSIS
plymouth-set-default-theme [OPTION...] [THEME]
DESCRIPTION
When called with a THEME argument, the plymouth-set-default-theme command changes the preferred boot theme and also performs the necessary
regeneration of the initial ramdisk (initrd) since plymouth is loaded from the boot loader from the initrd prior to the mounting of the
root filesystem.
If plymouth-set-default-theme is invoked with no options or parameters, it shows the currently selected theme by default. This output is
used by the helper scripts plymouth-generate-initrd and plymouth-update-initrd to set the proper theme in the initial ramdisk.
OPTIONS
The following options are understood:
-h, --help
Show summary of options.
-l, --list
List available themes.
-r, --reset
Reset to default theme.
-R, --rebuild-initrd
Rebuild initrd (necessary after changing theme).
SEE ALSO
grub(8), plymouth(8), plymouthd(8), plymouth(1), http://www.freedesktop.org/wiki/Software/Plymouth
plymouth PLYMOUTH-SET-DEFAU(1)