03-28-2019
When processing extremely large files you might consider using split first.
Then in multicore environments spawn several awks or greps to process it in parallel from shell script.
There are also GNU tools which offer parallelism without shell logic.
Should be a bit tougher to program, but processing time will be reduced significantly if you have cores and disks are fast to service.
Memory also comes in play, since split will read the files, and operating system will cache those files in memory, if the same is available.
Making those awks or greps processes much faster on read operations.
Of course, limit being free memory on the system and configuration of the file system caching in general.
In default configurations file system caching will be able to use a large portion free memory on most linux / unix systems i've seen.
Hope that helps
Regards
Peasant.
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IGAWK(1) Utility Commands IGAWK(1)
NAME
igawk - gawk with include files
SYNOPSIS
igawk [ all gawk options ] -f program-file [ -- ] file ...
igawk [ all gawk options ] [ -- ] program-text file ...
DESCRIPTION
Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1).
AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like
@include getopt.awk
in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path.
OPTIONS
See gawk(1) for a full description of the AWK language and the options that gawk supports.
EXAMPLES
cat << EOF > test.awk
@include getopt.awk
BEGIN {
while (getopt(ARGC, ARGV, "am:q") != -1)
...
}
EOF
igawk -f test.awk
SEE ALSO
gawk(1)
Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995.
AUTHOR
Arnold Robbins (arnold@skeeve.com).
Free Software Foundation Nov 3 1999 IGAWK(1)