HADOOP
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HADOOP
Links
- http://hadoop.apache.org/common/docs/r0.20.2/hdfs-default.html
- http://archive.cloudera.com/cdh/3/hadoop/hdfs-default.html
- https://ladd00.triumf.ca/hadoop/
Management
Create a name node
- TBW
- add to /etc/rc.local: firewall rules and service startup
iptables -F hadoop-namenode iptables -N hadoop-namenode iptables -A hadoop-namenode -p tcp -s 142.90.0.0/16 --dport 8020 -j ACCEPT iptables -A hadoop-namenode -p tcp -s 142.90.0.0/16 --dport 50070 -j ACCEPT iptables -A hadoop-namenode -p tcp --dport 8020 -j REJECT iptables -A hadoop-namenode -p tcp --dport 50070 -j REJECT iptables -A INPUT -j hadoop-namenode iptables -L -v service hadoop-0.20-namenode start
Create a data node
(only SL6 is supported. SL5 has problems with dead /hdfs mounts)
- install data node software
cd /triumfcs/trshare/olchansk/linux/hadoop/ rpm --import RPM-GPG-KEY-cloudera rpm -vh --install cdh3-repository-1.0-1.noarch.rpm-SL6 (cd $HOME; sh /triumfcs/trshare/olchansk/linux/hadoop/jdk-6u30-linux-x64-rpm.bin) cd ~ yum install hadoop"*"datanode hadoop"*"fuse hadoop"*"native chkconfig hadoop-0.20-datanode off
- FIXME: adjust hadoop UID/GID somehow - it is different on every machine! wrong, wrong, wrong!
- configure data node
ln -s /home/olchansk/sysadm/hadoop/conf.daq_test /etc/hadoop-0.20 alternatives --install /etc/hadoop-0.20/conf hadoop-0.20-conf /etc/hadoop-0.20/conf.daq_test 50 alternatives --display hadoop-0.20-conf mkdir /data8/hdfs_data chown -R hdfs.hdfs /data8/hdfs_data ln -s /data8/hdfs_data /datah
- add ladd08 to the hadoop cluster:
- cd /etc/hadoop/conf
- ### in hdfs-site.xml: add "/data8/hdfs_data" to dfs.data.dir
- ### in hdfs-site.xml: increase dfs.datanode.failed.volumes.tolerated by one (should be "number of dfs.data.dir entries" minus 1).
- add "ladd08.triumf.ca" to hosts
- add ladd08 IP address to topology.data
- ### restart the name server
- login to hdfs@nameserver, run: hadoop dfsadmin -refreshNodes
- add to /etc/rc.local: firewall rules, service startup and hdfs mount
iptables -F hadoop iptables -N hadoop iptables -A hadoop -p tcp -s 142.90.0.0/16 --dport 50010 -j ACCEPT iptables -A hadoop -p tcp -s 142.90.0.0/16 --dport 50020 -j ACCEPT iptables -A hadoop -p tcp -s 142.90.0.0/16 --dport 50075 -j ACCEPT iptables -A hadoop -p tcp --dport 50010 -j REJECT iptables -A hadoop -p tcp --dport 50020 -j REJECT iptables -A hadoop -p tcp --dport 50075 -j REJECT iptables -A INPUT -j hadoop iptables -L -v service hadoop-0.20-datanode start mkdir /hdfs unset LD_LIBRARY_PATH; hadoop-fuse-dfs dfs://ladd12:8020 /hdfs
debug functions
- start the data node: service hadoop-0.20-datanode restart
- look at the log file: tail -100 /usr/lib/hadoop-0.20/logs/hadoop-hadoop-datanode-ladd08.triumf.ca.log
- mount hdfs: unset LD_LIBRARY_PATH; hadoop-fuse-dfs dfs://ladd12:8020 /mnt/xxx
- watch name node: http://ladd12.triumf.ca:50070
- watch data node: http://ladd08.triumf.ca:50075
Performance
- cluster with 3 data nodes: ladd12 (quad-core i7-860), ladd08 (dual opteron 2GHz), ladd05 (dual-core Athlon 2.6 GHz)
- hdfs mounted on ladd12
- write benchmark:
ladd12:olchansk$ /usr/bin/time dd if=/dev/zero of=xxx bs=1024k count=1000 1000+0 records in 1000+0 records out 1048576000 bytes (1.0 GB) copied, 31.3406 s, 33.5 MB/s 0.00user 0.18system 0:31.43elapsed 0%CPU (0avgtext+0avgdata 7104maxresident)k 0inputs+0outputs (0major+483minor)pagefaults 0swaps ladd12:olchansk$ /usr/bin/time dd if=/dev/zero of=xxx2 bs=1024k count=10000 10000+0 records in 10000+0 records out 10485760000 bytes (10 GB) copied, 436.875 s, 24.0 MB/s 0.00user 1.72system 7:16.97elapsed 0%CPU (0avgtext+0avgdata 7104maxresident)k 0inputs+0outputs (0major+483minor)pagefaults 0swaps
ganglia reports peak network use 30 Mbytes/sec, ladd12: load 1, cpu use 10%, disk use 15%+15%busy; ladd05: load 2, cpu use 30%sys, 30%wait, disk use 15%+20%busy; ladd08: load 6, cpu use 30%sys, 70%wait, disk use 40%+40%busy.
- read benchmark:
ladd12:olchansk$ ls -l total 11391305 -rw-r--r-- 1 olchansk nobody 130360111 Dec 28 18:36 run21600sub00000.mid.gz -rw-r--r-- 1 olchansk nobody 1048576000 Jan 2 10:35 xxx -rw-r--r-- 1 olchansk nobody 10485760000 Jan 2 10:37 xxx2 ladd12:olchansk$ /usr/bin/time dd if=run21600sub00000.mid.gz of=/dev/null 254609+1 records in 254609+1 records out 130360111 bytes (130 MB) copied, 1.55497 s, 83.8 MB/s 0.02user 0.08system 0:01.69elapsed 6%CPU (0avgtext+0avgdata 3024maxresident)k 254632inputs+0outputs (1major+227minor)pagefaults 0swaps ladd12:olchansk$ ladd12:olchansk$ /usr/bin/time dd if=xxx of=/dev/null 2048000+0 records in 2048000+0 records out 1048576000 bytes (1.0 GB) copied, 11.4278 s, 91.8 MB/s 0.18user 0.69system 0:11.43elapsed 7%CPU (0avgtext+0avgdata 3008maxresident)k 2048000inputs+0outputs (0major+227minor)pagefaults 0swaps ladd12:olchansk$ ladd12:olchansk$ /usr/bin/time dd if=xxx2 of=/dev/null 20480000+0 records in 20480000+0 records out 10485760000 bytes (10 GB) copied, 130.188 s, 80.5 MB/s 1.68user 7.10system 2:10.19elapsed 6%CPU (0avgtext+0avgdata 3024maxresident)k 20480000inputs+0outputs (0major+228minor)pagefaults 0swaps
no network use, cpu use ladd12 is 10%+30%wait, disk use is 0% because all data was cached in memory: 10GB file, 16GB RAM.
Network ports
- data node ports:
[root@ladd08 ~]# diff xxx1 xxx2 | grep LISTEN > tcp 0 0 :::50020 :::* LISTEN > tcp 0 0 :::47860 :::* LISTEN > tcp 0 0 :::50010 :::* LISTEN > tcp 0 0 :::50075 :::* LISTEN
port 47860 is the java rmi server port, it is different on different machines and sometimes changes after restart. how to pin it to a fixed port number so I can firewall it?!?
- name node:
[root@ladd12 ~]# netstat -an | grep LISTEN | grep tcp > xxx2 [root@ladd12 ~]# diff xxx1 xxx2 < tcp 0 0 ::ffff:142.90.119.126:8020 :::* LISTEN < tcp 0 0 :::50070 :::* LISTEN < tcp 0 0 :::52745 :::* LISTEN
port 52745 is probably also the java rmi server port...