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quick integer CPU benchmark
This is a quick and dirty way to generate a (non-floating-point) CPU-bound task to benchmark. Adjust "20" to higher or lower values, as needed. As a benchmark this is probably a little less bogus than bogomips, and it will run anywhere 'bc' does.

FInd the 10 biggest files taking up disk space

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

Print entire field if string is detected in column
It searches for a specific value in the specified column and if it finds it it'll print the whole field/row. Similarly, if you don't know what you're looking for exactly but want to exclude something you're already aware of, you can exclude that "something: awk '{ if ($column != "string") print $0}'

umount --rbind mount with submounts
Original: https://bugzilla.redhat.com/show_bug.cgi?id=194342

Speed up upgrades for a debian/ubuntu based system.
Please install aria2c before you try the above command. On ubuntu the command to install aria2c would be: $sudo aptitude install aria2

Put public IP address in a variable

SED - Substitute string in next line
source: http://sed.sourceforge.net/sed1line.txt

count IPv4 connections per IP
usefull in case of abuser/DoS attacks.

Create the signature base string required for a Twitter stream feed
This is the SECOND command in a set for five that are needed for a Twitter stream feed. This command creates variable "b", the so-called "base string" required for oauth in Twitter stream feed requests. (The 256 char limit prevents giving it a better name) We use five environment variables created by a previous step: id, k1, once, ts and k3. The five environment variables are created in a separate command, please see my other commands. For more information on the signature base string, see dev.twitter.com/apps, click on any app (or create a new one) and then go to the "OAuth Tool" tab.


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