iostat service time (svctm) rule of thumb
iostat service time is a very useful metric when analyzing disk performance and finding bottlenecks service time is essentially the inverse of IOPs so if an operation takes 1ms to service, thenRead More…
iostat service time is a very useful metric when analyzing disk performance and finding bottlenecks service time is essentially the inverse of IOPs so if an operation takes 1ms to service, thenRead More…
function displaytime { local T=$1 local D=$((T/60/60/24)) local H=$((T/60/60%24)) local M=$((T/60%60)) local S=$((T%60)) (( $D > 0 )) && printf ‘%d days ‘ $D (( $H > 0 )) && printf ‘%dRead More…
We need to run ifconfig and look for the status line. Remember this about ifconfig output: * if “status: active“, the port is linked up and sending traffic (now you just needRead More…
If your system gzips and rotates your logs. You can use this trick to search thru all of them. # zgrep -i — “SEARCHTERM” $(ls -1Str /var/log/messages*) Another way # zgrep -iRead More…
Got info from here: https://stackoverflow.com/questions/18363833/how-can-i-list-upnp-server-renderer-in-command-line-console-mode-on-linux Get the Upnp test tools # apt-get install gupnp-tools Example 1: Find all Upnp devices (note their target names start with urn:…. It will hint at what service itRead More…
You can use bash to do simple substitutions of variables, just like you can with sed. The bash trick turns out to take up less characters (bytes). Lets set some variable VAR1="thisRead More…
Imagine a file list, list.txt, like this one image1.jpg image2.jpg image3.jpg Naturally you could deal with it like so cat list.txt | while read i; do FILE="$i" dosomething "$FILE" done Or justRead More…
Here I show you how to repeat a command until it finishes successfully. This should only be done with programs that support resume and also have legit exit codes (or else theyRead More…
When you are running a command hit Control-T anytime, its very useful when a command looks stuck. It causes the kernel to spit out a line similar to the following: load: 0.69Read More…
Screen the app that can split screens like so, is not too intuitive when it comes to scrolling thru your bash shell. Notice where the cursor is in the diagram below, itsRead More…