While the output of the top command displayed, press F, which will display all fields available for sorting, press n (which is for sorting the processes by Memory) and press enter.

press c, which will display full pathname of running processes

press 1 (number one), which will display the performance data of the individual CPUs.

If you have problems to delete many files in a folder using rm * because you get the error that the argument list is to long you can use the combination of ls and xargs to get rid of the files.

Instead of
rm *

Solution:
ls | xargs rm -f

#!/bin/sh

for dbname in `mysqlshow | awk '{print $2}'`
do
mysqlcheck $dbname ticket -Fq
done

# call this shell script and find the errors
time sh check.sh | grep error

When there is an issue, We should gather some preliminary data to analyze first.

tee 'output.txt';
SHOW GLOBAL STATUS;
SHOW ENGINE INNODB STATUS;
SHOW FULL PROCESSLIST;
SELECT SLEEP(60);
SHOW GLOBAL STATUS;
SHOW ENGINE INNODB STATUS;
SHOW FULL PROCESSLIST;

SHOW GLOBAL VARIABLES;
notee;

Study the 'output.txt' file. Also the my.cnf and slow query log
From the OS;

free -m
ps aux
df -h

iostat -x 1 5
vmstat 1 5
top -b -n 3
mysql> show global status;

You can get information about the make, model and serial number of the equipment as shown below:
# dmidecode -t system

What is the maximum RAM supported by the system?
# dmidecode -t 16

Currently installed RAM
# cat /proc/meminfo | grep -i memtotal

Memory slots occupied
# /usr/sbin/dmidecode -t 17 | grep -i size

// know more about running processes
# dstat

Consider setting up a simple Git alias for common but complex Git command that you type frequently.

git config --global alias.show-graph 'log --graph --abbrev-commit --pretty=oneline'

It is incredibly easy to migrate from MySQL to PostgreSQL. Just migrate your schema first (leaving foreign keys out until after restore) and then the mysqldump files are almost perfectly compatible with PostgreSQL when using:

mysqldump --compatible=postgresql --no-create-db --no-create-info --add-locks=false --quote-names=false --complete-insert=true

I just had to convert \' to two single quotes and fix MySQL's infamous null dates (0000-00-00 00:00:00) to be true nulls and was able to pipe the backup right into psql.

sed -e "s/\\\'/\'\'/g" -e "s/\'0000-00-00 00:00:00\'/null/g" backup.sql > output.sql

Following my.cnf parameter is highly recommended on high configuration machine. This will make importing myisam only data much faster.

#datadir=/var/lib/mysql
datadir=/mnt/data/mysql/
user=root
skip-innodb
default-storage-engine=myisam
key-buffer=1G
bulk_insert_buffer_size=1G
myisam_max_sort_file_size=20G

tmpdir=/mnt/data/mysql

Add the following to the .gitconfig file in your $HOME directory.

[alias]
co = checkout
ci = commit
st = status
br = branch
hist = log --pretty=format:\"%h %ad | %s%d [%an]\" --graph --date=short
type = cat-file -t
dump = cat-file -p

Here is a quick way to send files from any server where mutt is installed.

echo "Attaching a file " | mutt -s "file attachment" -a /root/somefile.txt -- your.name@gmail.com