Web Soultion

oracle session Hint

select * from v$resource_limit where resource_name in ('processes','sessions');

centos 7 : cpu, mem info Hint

# free # cat /proc/meminfo | grep MemTotal # grep -c processor /proc/cpuinfo # grep ^processor /proc/cpuinfo | wc -l # grep 'cpu cores' /proc/cpuinfo | tail -1

apache : concurrent connection Hint

80 port concurrent connection count # netstat -nap | grep :80 | grep ESTABLISHED | wc -l 80 port connection count # netstat -n|grep -F :80|egrep '(ESTAB|SYN)'|awk '{print $5}'|sed 's/:[0-9]*//'|sort -u|wc -l all port connection count # netstat -nap | grep ESTABLISHED | wc -l

Excel vs Unix Timestemp : excel datevalue to java dateformat Hint!

Unix Timestamp from 1970 Excel Timestamp from 1900 Gap : (1970-1900) Days = 25569 Days String rtn = ""; try{ DateFormat format = new SimpleDateFormat("yyyyMMdd"); //format.setTimeZone(TimeZone.getTimeZone("UTC")); double excelDays = Double.parseDouble((String)valv.elementAt(0)); double unixDays = (excelDays-25569); java.util.Date unixTime = new java.util.Date((long) ( 86400000l * unixDays)); rtn = format.format(unixTime); out.println(rtn); } catch(Exception e) {}

centos 7 : install node.js

# yum repolist check epel .... # yum install npm nodejs # node -v # npm -v

mac os x : mov to mp4, ffmpeg -i

$ brew install ffmpeg $ ffmpeg -i /path/file.mov /path/file.mp4

centos 7 : ntpd kernel level time sync Hint, NTP synchronized timedatectl

centos 7 NTP synchronized # timedatectl status # timedatectl set-ntp true More Hint! # timedatectl | grep -i 'time zone' # ls -l /etc/localtime # timedatectl list-timezones | grep Asia/Seoul # timedatectl set-timezone Asia/Seoul Asia/Seoul => KST yum install -y ntp firewall-cmd --add-service=ntp --permanent firewall-cmd --reload systemctl enable ntpd systemctl […]