大數(shù)據(jù)之----hadoop中各pid進(jìn)程號(hào)之快速定位

經(jīng)常管理和監(jiān)控，需要進(jìn)行shell編程，直接對(duì)進(jìn)程kill或者重啟操作。我們需要進(jìn)行快速定位到每個(gè)進(jìn)程的pid號(hào)
pid默認(rèn)存儲(chǔ)在/tmp目錄

pid內(nèi)容為進(jìn)程號(hào)

ps -ef|grep hadoop 出現(xiàn)PID A,B,C 可能誤殺B,C

[hadoop@hadoop000 sbin]$ cat hadoop-daemon.sh |grep pid
#HADOOPPIDDIR The pid files are stored. /tmp by default.
pid=$HADOOP_PID_DIR/hadoop-$HADOOP_IDENT_STRING-$command.pid
if [ -f $pid ]; then
if kill -0 cat $pid > /dev/null 2>&1; then
echo $command running as process cat $pid. Stop it first.
echo $! > $pid
if [ -f $pid ]; then
TARGET_PID=cat $pid
rm -f $pid
官方給的sh腳本中，也是通過讀取pid文件內(nèi)容作為進(jìn)程kill對(duì)象

我們直接對(duì)pid文件的數(shù)字就是我們對(duì)于的進(jìn)程pid

[hadoop@hadoop01 tmp]$ ls *.pid
hadoop-hadoop-datanode.pid yarn-hadoop-nodemanager.pid
hadoop-hadoop-namenode.pid yarn-hadoop-resourcemanager.pid
hadoop-hadoop-secondarynamenode.pid yarn-hdfs-resourcemanager.pid
[hadoop@hadoop01 tmp]$
[hadoop@hadoop01 tmp]$ cat hadoop-hadoop-datanode.pid
8990
[hadoop@hadoop01 tmp]$ jps
12060 Jps
9193 SecondaryNameNode
9566 NodeManager
8990 DataNode
9450 ResourceManager

kill -0 cat /tmp/hadoop-hadoop-datanode.pid ---shell常用kill pid方式`