Some Linux Concepts.
How to check the utilisation of each cores: mpstat -P ALL 1 & lscpu or cat /proc/cpuinfo ps -aeF gives the details of which core ID is being used for a process. top -H -p => gives all the details of threads of all the processes. lsof -t => Gives the PID of a file name. netstat -a => all ; listening + established; -n => suppress host/port name resolution; -t => only tcp ; -p => program name; -r routing; -i interface Find files smaller than 2K: find -type f -mindepth 2 -size -1c Find files which are not older than 2 days: find -type f -mtime -2 stat zzz (Gives all the statistics of a file); stat %i ; %F; %G; %U; %b ; atime => when it was last accessed , mtime => when the file was last modified, ctime when the file was last changed (changed means file attributes were changed) Unix File system: A directory has name & a number; number refers to a