Frequently used unix commands by Greenplum DBA's

11.uptime

12. ps

13. free

14. iostat

15.sar

16. mpstat

17.pmap

18. /proc file system - various kernet stats

# cat /proc/cpuinfo

# cat /proc/meminfo

# cat /proc/zoneinfo

# cat /proc/mounts

# cat /proc/version

19. lsof

Find out total space used by log files of primary segment databases

[gpadmin@sachi ~]$gpssh -f $GPHOME/hosts.seg "du –h -s /data[12]/primary/gpseg*/pg_log*"

$(date +%s)

start_time=$(date +%s)

end_time=$(date +%s)

duration=`expr $end_time - $start_time`

echo `expr $difference / 3600`:`expr "(" $difference / 60 ")" % 60`:`expr $difference % 60`

List files in current directory and its size

for i in `ls -lh|awk {'print $9,$5}'`; do echo $i; done

20. last

21. df

22. du

23. kill

24. traceroute

25. rsync

26. rpm

27. tar

28. pwd

29. lsb_rlease -a

30. uname -a  [-prints the name, version and other details about the current machine and the operating system running on it.]

Find out total space used by backup files of primary segment databases

[gpadmin@sachi ~]$gpssh -f $GPHOME/hosts.seg "du –h -s /data[12]/primary/gpseg*/db_dumps*"

Change all uppercase to lowercase with vi?

:%s/.*/\L&/

Conversely, :%s/.*/\U&/ will change all the characters to uppercase.

List all directory and subdirectory

ls -lDR | grep ':$' | head |sed -e 's/:$//'

datediff() {

 d1=$(date -d "$1" +%s)

 d2=$(date -d "$2" +%s)

 echo $(( (d1 - d2) / 86400 )) days

 }

timespent() {

 d1=$(date -d "$1" +%s)

 d2=$(date -d "$2" +%s)

 echo $(( (d1 - d2) )) seconds

 }