Thanks! I ll see what I can find out. On Fri, Apr 17, 2009 at 4:55 AM, jason hadoop <jason.had...@gmail.com>wrote:
> The firewall was run at system startup, I think there was a > /etc/sysconfig/iptables file present which triggered the firewall. > I don't currently have access to any centos 5 machines so I can't easily > check. > > > > On Thu, Apr 16, 2009 at 6:54 PM, jason hadoop <jason.had...@gmail.com > >wrote: > > > The kickstart script was something that the operations staff was using to > > initialize new machines, I never actually saw the script, just figured > out > > that there was a firewall in place. > > > > > > > > On Thu, Apr 16, 2009 at 1:28 PM, Mithila Nagendra <mnage...@asu.edu > >wrote: > > > >> Jason: the kickstart script - was it something you wrote or is it run > when > >> the system turns on? > >> Mithila > >> > >> On Thu, Apr 16, 2009 at 1:06 AM, Mithila Nagendra <mnage...@asu.edu> > >> wrote: > >> > >> > Thanks Jason! Will check that out. > >> > Mithila > >> > > >> > > >> > On Thu, Apr 16, 2009 at 5:23 AM, jason hadoop <jason.had...@gmail.com > >> >wrote: > >> > > >> >> Double check that there is no firewall in place. > >> >> At one point a bunch of new machines were kickstarted and placed in a > >> >> cluster and they all failed with something similar. > >> >> It turned out the kickstart script turned enabled the firewall with a > >> rule > >> >> that blocked ports in the 50k range. > >> >> It took us a while to even think to check that was not a part of our > >> >> normal > >> >> machine configuration > >> >> > >> >> On Wed, Apr 15, 2009 at 11:04 AM, Mithila Nagendra <mnage...@asu.edu > > > >> >> wrote: > >> >> > >> >> > Hi Aaron > >> >> > I will look into that thanks! > >> >> > > >> >> > I spoke to the admin who overlooks the cluster. He said that the > >> gateway > >> >> > comes in to the picture only when one of the nodes communicates > with > >> a > >> >> node > >> >> > outside of the cluster. But in my case the communication is carried > >> out > >> >> > between the nodes which all belong to the same cluster. > >> >> > > >> >> > Mithila > >> >> > > >> >> > On Wed, Apr 15, 2009 at 8:59 PM, Aaron Kimball <aa...@cloudera.com > > > >> >> wrote: > >> >> > > >> >> > > Hi, > >> >> > > > >> >> > > I wrote a blog post a while back about connecting nodes via a > >> gateway. > >> >> > See > >> >> > > > >> >> > > >> >> > >> > http://www.cloudera.com/blog/2008/12/03/securing-a-hadoop-cluster-through-a-gateway/ > >> >> > > > >> >> > > This assumes that the client is outside the gateway and all > >> >> > > datanodes/namenode are inside, but the same principles apply. > >> You'll > >> >> just > >> >> > > need to set up ssh tunnels from every datanode to the namenode. > >> >> > > > >> >> > > - Aaron > >> >> > > > >> >> > > > >> >> > > On Wed, Apr 15, 2009 at 10:19 AM, Ravi Phulari < > >> >> rphul...@yahoo-inc.com > >> >> > >wrote: > >> >> > > > >> >> > >> Looks like your NameNode is down . > >> >> > >> Verify if hadoop process are running ( jps should show you all > >> java > >> >> > >> running process). > >> >> > >> If your hadoop process are running try restarting your hadoop > >> process > >> >> . > >> >> > >> I guess this problem is due to your fsimage not being correct . > >> >> > >> You might have to format your namenode. > >> >> > >> Hope this helps. > >> >> > >> > >> >> > >> Thanks, > >> >> > >> -- > >> >> > >> Ravi > >> >> > >> > >> >> > >> > >> >> > >> On 4/15/09 10:15 AM, "Mithila Nagendra" <mnage...@asu.edu> > wrote: > >> >> > >> > >> >> > >> The log file runs into thousands of line with the same message > >> being > >> >> > >> displayed every time. > >> >> > >> > >> >> > >> On Wed, Apr 15, 2009 at 8:10 PM, Mithila Nagendra < > >> mnage...@asu.edu> > >> >> > >> wrote: > >> >> > >> > >> >> > >> > The log file : hadoop-mithila-datanode-node19.log.2009-04-14 > has > >> >> the > >> >> > >> > following in it: > >> >> > >> > > >> >> > >> > 2009-04-14 10:08:11,499 INFO org.apache.hadoop.dfs.DataNode: > >> >> > >> STARTUP_MSG: > >> >> > >> > /************************************************************ > >> >> > >> > STARTUP_MSG: Starting DataNode > >> >> > >> > STARTUP_MSG: host = node19/127.0.0.1 > >> >> > >> > STARTUP_MSG: args = [] > >> >> > >> > STARTUP_MSG: version = 0.18.3 > >> >> > >> > STARTUP_MSG: build = > >> >> > >> > > >> https://svn.apache.org/repos/asf/hadoop/core/branches/branch-0.18-r > >> >> > >> > 736250; compiled by 'ndaley' on Thu Jan 22 23:12:08 UTC 2009 > >> >> > >> > ************************************************************/ > >> >> > >> > 2009-04-14 10:08:12,915 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 0 > time(s). > >> >> > >> > 2009-04-14 10:08:13,925 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 1 > time(s). > >> >> > >> > 2009-04-14 10:08:14,935 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 2 > time(s). > >> >> > >> > 2009-04-14 10:08:15,945 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 3 > time(s). > >> >> > >> > 2009-04-14 10:08:16,955 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 4 > time(s). > >> >> > >> > 2009-04-14 10:08:17,965 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 5 > time(s). > >> >> > >> > 2009-04-14 10:08:18,975 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 6 > time(s). > >> >> > >> > 2009-04-14 10:08:19,985 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 7 > time(s). > >> >> > >> > 2009-04-14 10:08:20,995 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 8 > time(s). > >> >> > >> > 2009-04-14 10:08:22,005 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 9 > time(s). > >> >> > >> > 2009-04-14 10:08:22,008 INFO org.apache.hadoop.ipc.RPC: Server > >> at > >> >> > >> node18/ > >> >> > >> > 192.168.0.18:54310 not available yet, Zzzzz... > >> >> > >> > 2009-04-14 10:08:24,025 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 0 > time(s). > >> >> > >> > 2009-04-14 10:08:25,035 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 1 > time(s). > >> >> > >> > 2009-04-14 10:08:26,045 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 2 > time(s). > >> >> > >> > 2009-04-14 10:08:27,055 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 3 > time(s). > >> >> > >> > 2009-04-14 10:08:28,065 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 4 > time(s). > >> >> > >> > 2009-04-14 10:08:29,075 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 5 > time(s). > >> >> > >> > 2009-04-14 10:08:30,085 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 6 > time(s). > >> >> > >> > 2009-04-14 10:08:31,095 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 7 > time(s). > >> >> > >> > 2009-04-14 10:08:32,105 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 8 > time(s). > >> >> > >> > 2009-04-14 10:08:33,115 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 9 > time(s). > >> >> > >> > 2009-04-14 10:08:33,116 INFO org.apache.hadoop.ipc.RPC: Server > >> at > >> >> > >> node18/ > >> >> > >> > 192.168.0.18:54310 not available yet, Zzzzz... > >> >> > >> > 2009-04-14 10:08:35,135 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 0 > time(s). > >> >> > >> > 2009-04-14 10:08:36,145 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 1 > time(s). > >> >> > >> > 2009-04-14 10:08:37,155 INFO org.apache.hadoop.ipc.Client: > >> Retrying > >> >> > >> connect > >> >> > >> > to server: node18/192.168.0.18:54310. Already tried 2 > time(s). > >> >> > >> > > >> >> > >> > > >> >> > >> > Hmmm I still cant figure it out.. > >> >> > >> > > >> >> > >> > Mithila > >> >> > >> > > >> >> > >> > > >> >> > >> > On Tue, Apr 14, 2009 at 10:22 PM, Mithila Nagendra < > >> >> mnage...@asu.edu > >> >> > >> >wrote: > >> >> > >> > > >> >> > >> >> Also, Would the way the port is accessed change if all these > >> node > >> >> are > >> >> > >> >> connected through a gateway? I mean in the hadoop-site.xml > >> file? > >> >> The > >> >> > >> Ubuntu > >> >> > >> >> systems we worked with earlier didnt have a gateway. > >> >> > >> >> Mithila > >> >> > >> >> > >> >> > >> >> On Tue, Apr 14, 2009 at 9:48 PM, Mithila Nagendra < > >> >> mnage...@asu.edu > >> >> > >> >wrote: > >> >> > >> >> > >> >> > >> >>> Aaron: Which log file do I look into - there are alot of > them. > >> >> Here > >> >> > s > >> >> > >> >>> what the error looks like: > >> >> > >> >>> [mith...@node19:~]$ cd hadoop > >> >> > >> >>> [mith...@node19:~/hadoop]$ bin/hadoop dfs -ls > >> >> > >> >>> 09/04/14 10:09:29 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 0 time(s). > >> >> > >> >>> 09/04/14 10:09:30 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 1 time(s). > >> >> > >> >>> 09/04/14 10:09:31 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 2 time(s). > >> >> > >> >>> 09/04/14 10:09:32 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 3 time(s). > >> >> > >> >>> 09/04/14 10:09:33 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 4 time(s). > >> >> > >> >>> 09/04/14 10:09:34 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 5 time(s). > >> >> > >> >>> 09/04/14 10:09:35 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 6 time(s). > >> >> > >> >>> 09/04/14 10:09:36 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 7 time(s). > >> >> > >> >>> 09/04/14 10:09:37 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 8 time(s). > >> >> > >> >>> 09/04/14 10:09:38 INFO ipc.Client: Retrying connect to > server: > >> >> > node18/ > >> >> > >> >>> 192.168.0.18:54310. Already tried 9 time(s). > >> >> > >> >>> Bad connection to FS. command aborted. > >> >> > >> >>> > >> >> > >> >>> Node19 is a slave and Node18 is the master. > >> >> > >> >>> > >> >> > >> >>> Mithila > >> >> > >> >>> > >> >> > >> >>> > >> >> > >> >>> > >> >> > >> >>> On Tue, Apr 14, 2009 at 8:53 PM, Aaron Kimball < > >> >> aa...@cloudera.com > >> >> > >> >wrote: > >> >> > >> >>> > >> >> > >> >>>> Are there any error messages in the log files on those > nodes? > >> >> > >> >>>> - Aaron > >> >> > >> >>>> > >> >> > >> >>>> On Tue, Apr 14, 2009 at 9:03 AM, Mithila Nagendra < > >> >> > mnage...@asu.edu> > >> >> > >> >>>> wrote: > >> >> > >> >>>> > >> >> > >> >>>> > I ve drawn a blank here! Can't figure out what s wrong > with > >> >> the > >> >> > >> ports. > >> >> > >> >>>> I > >> >> > >> >>>> > can > >> >> > >> >>>> > ssh between the nodes but cant access the DFS from the > >> slaves > >> >> - > >> >> > >> says > >> >> > >> >>>> "Bad > >> >> > >> >>>> > connection to DFS". Master seems to be fine. > >> >> > >> >>>> > Mithila > >> >> > >> >>>> > > >> >> > >> >>>> > On Tue, Apr 14, 2009 at 4:28 AM, Mithila Nagendra < > >> >> > >> mnage...@asu.edu> > >> >> > >> >>>> > wrote: > >> >> > >> >>>> > > >> >> > >> >>>> > > Yes I can.. > >> >> > >> >>>> > > > >> >> > >> >>>> > > > >> >> > >> >>>> > > On Mon, Apr 13, 2009 at 5:12 PM, Jim Twensky < > >> >> > >> jim.twen...@gmail.com > >> >> > >> >>>> > >wrote: > >> >> > >> >>>> > > > >> >> > >> >>>> > >> Can you ssh between the nodes? > >> >> > >> >>>> > >> > >> >> > >> >>>> > >> -jim > >> >> > >> >>>> > >> > >> >> > >> >>>> > >> On Mon, Apr 13, 2009 at 6:49 PM, Mithila Nagendra < > >> >> > >> >>>> mnage...@asu.edu> > >> >> > >> >>>> > >> wrote: > >> >> > >> >>>> > >> > >> >> > >> >>>> > >> > Thanks Aaron. > >> >> > >> >>>> > >> > Jim: The three clusters I setup had ubuntu running > on > >> >> them > >> >> > and > >> >> > >> >>>> the dfs > >> >> > >> >>>> > >> was > >> >> > >> >>>> > >> > accessed at port 54310. The new cluster which I ve > >> setup > >> >> has > >> >> > >> Red > >> >> > >> >>>> Hat > >> >> > >> >>>> > >> Linux > >> >> > >> >>>> > >> > release 7.2 (Enigma)running on it. Now when I try to > >> >> access > >> >> > >> the > >> >> > >> >>>> dfs > >> >> > >> >>>> > from > >> >> > >> >>>> > >> > one > >> >> > >> >>>> > >> > of the slaves i get the following response: dfs > cannot > >> be > >> >> > >> >>>> accessed. > >> >> > >> >>>> > When > >> >> > >> >>>> > >> I > >> >> > >> >>>> > >> > access the DFS throught the master there s no > problem. > >> So > >> >> I > >> >> > >> feel > >> >> > >> >>>> there > >> >> > >> >>>> > a > >> >> > >> >>>> > >> > problem with the port. Any ideas? I did check the > list > >> of > >> >> > >> slaves, > >> >> > >> >>>> it > >> >> > >> >>>> > >> looks > >> >> > >> >>>> > >> > fine to me. > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > Mithila > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > On Mon, Apr 13, 2009 at 2:58 PM, Jim Twensky < > >> >> > >> >>>> jim.twen...@gmail.com> > >> >> > >> >>>> > >> > wrote: > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > > Mithila, > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > You said all the slaves were being utilized in the > 3 > >> >> node > >> >> > >> >>>> cluster. > >> >> > >> >>>> > >> Which > >> >> > >> >>>> > >> > > application did you run to test that and what was > >> your > >> >> > input > >> >> > >> >>>> size? > >> >> > >> >>>> > If > >> >> > >> >>>> > >> you > >> >> > >> >>>> > >> > > tried the word count application on a 516 MB input > >> file > >> >> on > >> >> > >> both > >> >> > >> >>>> > >> cluster > >> >> > >> >>>> > >> > > setups, than some of your nodes in the 15 node > >> cluster > >> >> may > >> >> > >> not > >> >> > >> >>>> be > >> >> > >> >>>> > >> running > >> >> > >> >>>> > >> > > at > >> >> > >> >>>> > >> > > all. Generally, one map job is assigned to each > >> input > >> >> > split > >> >> > >> and > >> >> > >> >>>> if > >> >> > >> >>>> > you > >> >> > >> >>>> > >> > are > >> >> > >> >>>> > >> > > running your cluster with the defaults, the splits > >> are > >> >> 64 > >> >> > MB > >> >> > >> >>>> each. I > >> >> > >> >>>> > >> got > >> >> > >> >>>> > >> > > confused when you said the Namenode seemed to do > all > >> >> the > >> >> > >> work. > >> >> > >> >>>> Can > >> >> > >> >>>> > you > >> >> > >> >>>> > >> > > check > >> >> > >> >>>> > >> > > conf/slaves and make sure you put the names of all > >> task > >> >> > >> >>>> trackers > >> >> > >> >>>> > >> there? I > >> >> > >> >>>> > >> > > also suggest comparing both clusters with a larger > >> >> input > >> >> > >> size, > >> >> > >> >>>> say > >> >> > >> >>>> > at > >> >> > >> >>>> > >> > least > >> >> > >> >>>> > >> > > 5 GB, to really see a difference. > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > Jim > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > On Mon, Apr 13, 2009 at 4:17 PM, Aaron Kimball < > >> >> > >> >>>> aa...@cloudera.com> > >> >> > >> >>>> > >> > wrote: > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > > in hadoop-*-examples.jar, use "randomwriter" to > >> >> generate > >> >> > >> the > >> >> > >> >>>> data > >> >> > >> >>>> > >> and > >> >> > >> >>>> > >> > > > "sort" > >> >> > >> >>>> > >> > > > to sort it. > >> >> > >> >>>> > >> > > > - Aaron > >> >> > >> >>>> > >> > > > > >> >> > >> >>>> > >> > > > On Sun, Apr 12, 2009 at 9:33 PM, Pankil Doshi < > >> >> > >> >>>> > forpan...@gmail.com> > >> >> > >> >>>> > >> > > wrote: > >> >> > >> >>>> > >> > > > > >> >> > >> >>>> > >> > > > > Your data is too small I guess for 15 clusters > >> ..So > >> >> it > >> >> > >> >>>> might be > >> >> > >> >>>> > >> > > overhead > >> >> > >> >>>> > >> > > > > time of these clusters making your total MR > jobs > >> >> more > >> >> > >> time > >> >> > >> >>>> > >> consuming. > >> >> > >> >>>> > >> > > > > I guess you will have to try with larger set > of > >> >> data.. > >> >> > >> >>>> > >> > > > > > >> >> > >> >>>> > >> > > > > Pankil > >> >> > >> >>>> > >> > > > > On Sun, Apr 12, 2009 at 6:54 PM, Mithila > >> Nagendra < > >> >> > >> >>>> > >> mnage...@asu.edu> > >> >> > >> >>>> > >> > > > > wrote: > >> >> > >> >>>> > >> > > > > > >> >> > >> >>>> > >> > > > > > Aaron > >> >> > >> >>>> > >> > > > > > > >> >> > >> >>>> > >> > > > > > That could be the issue, my data is just > 516MB > >> - > >> >> > >> wouldn't > >> >> > >> >>>> this > >> >> > >> >>>> > >> see > >> >> > >> >>>> > >> > a > >> >> > >> >>>> > >> > > > bit > >> >> > >> >>>> > >> > > > > of > >> >> > >> >>>> > >> > > > > > speed up? > >> >> > >> >>>> > >> > > > > > Could you guide me to the example? I ll run > my > >> >> > cluster > >> >> > >> on > >> >> > >> >>>> it > >> >> > >> >>>> > and > >> >> > >> >>>> > >> > see > >> >> > >> >>>> > >> > > > what > >> >> > >> >>>> > >> > > > > I > >> >> > >> >>>> > >> > > > > > get. Also for my program I had a java timer > >> >> running > >> >> > to > >> >> > >> >>>> record > >> >> > >> >>>> > >> the > >> >> > >> >>>> > >> > > time > >> >> > >> >>>> > >> > > > > > taken > >> >> > >> >>>> > >> > > > > > to complete execution. Does Hadoop have an > >> >> inbuilt > >> >> > >> timer? > >> >> > >> >>>> > >> > > > > > > >> >> > >> >>>> > >> > > > > > Mithila > >> >> > >> >>>> > >> > > > > > > >> >> > >> >>>> > >> > > > > > On Mon, Apr 13, 2009 at 1:13 AM, Aaron > Kimball > >> < > >> >> > >> >>>> > >> aa...@cloudera.com > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > > > wrote: > >> >> > >> >>>> > >> > > > > > > >> >> > >> >>>> > >> > > > > > > Virtually none of the examples that ship > >> with > >> >> > Hadoop > >> >> > >> >>>> are > >> >> > >> >>>> > >> designed > >> >> > >> >>>> > >> > > to > >> >> > >> >>>> > >> > > > > > > showcase its speed. Hadoop's speedup comes > >> from > >> >> > its > >> >> > >> >>>> ability > >> >> > >> >>>> > to > >> >> > >> >>>> > >> > > > process > >> >> > >> >>>> > >> > > > > > very > >> >> > >> >>>> > >> > > > > > > large volumes of data (starting around, > say, > >> >> tens > >> >> > of > >> >> > >> GB > >> >> > >> >>>> per > >> >> > >> >>>> > >> job, > >> >> > >> >>>> > >> > > and > >> >> > >> >>>> > >> > > > > > going > >> >> > >> >>>> > >> > > > > > > up in orders of magnitude from there). So > if > >> >> you > >> >> > are > >> >> > >> >>>> timing > >> >> > >> >>>> > >> the > >> >> > >> >>>> > >> > pi > >> >> > >> >>>> > >> > > > > > > calculator (or something like that), its > >> >> results > >> >> > >> won't > >> >> > >> >>>> > >> > necessarily > >> >> > >> >>>> > >> > > be > >> >> > >> >>>> > >> > > > > > very > >> >> > >> >>>> > >> > > > > > > consistent. If a job doesn't have enough > >> >> fragments > >> >> > >> of > >> >> > >> >>>> data > >> >> > >> >>>> > to > >> >> > >> >>>> > >> > > > allocate > >> >> > >> >>>> > >> > > > > > one > >> >> > >> >>>> > >> > > > > > > per each node, some of the nodes will also > >> just > >> >> go > >> >> > >> >>>> unused. > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > The best example for you to run is to use > >> >> > >> randomwriter > >> >> > >> >>>> to > >> >> > >> >>>> > fill > >> >> > >> >>>> > >> up > >> >> > >> >>>> > >> > > > your > >> >> > >> >>>> > >> > > > > > > cluster with several GB of random data and > >> then > >> >> > run > >> >> > >> the > >> >> > >> >>>> sort > >> >> > >> >>>> > >> > > program. > >> >> > >> >>>> > >> > > > > If > >> >> > >> >>>> > >> > > > > > > that doesn't scale up performance from 3 > >> nodes > >> >> to > >> >> > >> 15, > >> >> > >> >>>> then > >> >> > >> >>>> > >> you've > >> >> > >> >>>> > >> > > > > > > definitely > >> >> > >> >>>> > >> > > > > > > got something strange going on. > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > - Aaron > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > On Sun, Apr 12, 2009 at 8:39 AM, Mithila > >> >> Nagendra > >> >> > < > >> >> > >> >>>> > >> > > mnage...@asu.edu> > >> >> > >> >>>> > >> > > > > > > wrote: > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > > Hey all > >> >> > >> >>>> > >> > > > > > > > I recently setup a three node hadoop > >> cluster > >> >> and > >> >> > >> ran > >> >> > >> >>>> an > >> >> > >> >>>> > >> > examples > >> >> > >> >>>> > >> > > on > >> >> > >> >>>> > >> > > > > it. > >> >> > >> >>>> > >> > > > > > > It > >> >> > >> >>>> > >> > > > > > > > was pretty fast, and all the three nodes > >> were > >> >> > >> being > >> >> > >> >>>> used > >> >> > >> >>>> > (I > >> >> > >> >>>> > >> > > checked > >> >> > >> >>>> > >> > > > > the > >> >> > >> >>>> > >> > > > > > > log > >> >> > >> >>>> > >> > > > > > > > files to make sure that the slaves are > >> >> > utilized). > >> >> > >> >>>> > >> > > > > > > > > >> >> > >> >>>> > >> > > > > > > > Now I ve setup another cluster > consisting > >> of > >> >> 15 > >> >> > >> >>>> nodes. I > >> >> > >> >>>> > ran > >> >> > >> >>>> > >> > the > >> >> > >> >>>> > >> > > > same > >> >> > >> >>>> > >> > > > > > > > example, but instead of speeding up, the > >> >> > >> map-reduce > >> >> > >> >>>> task > >> >> > >> >>>> > >> seems > >> >> > >> >>>> > >> > to > >> >> > >> >>>> > >> > > > > take > >> >> > >> >>>> > >> > > > > > > > forever! The slaves are not being used > for > >> >> some > >> >> > >> >>>> reason. > >> >> > >> >>>> > This > >> >> > >> >>>> > >> > > second > >> >> > >> >>>> > >> > > > > > > cluster > >> >> > >> >>>> > >> > > > > > > > has a lower, per node processing power, > >> but > >> >> > should > >> >> > >> >>>> that > >> >> > >> >>>> > make > >> >> > >> >>>> > >> > any > >> >> > >> >>>> > >> > > > > > > > difference? > >> >> > >> >>>> > >> > > > > > > > How can I ensure that the data is being > >> >> mapped > >> >> > to > >> >> > >> all > >> >> > >> >>>> the > >> >> > >> >>>> > >> > nodes? > >> >> > >> >>>> > >> > > > > > > Presently, > >> >> > >> >>>> > >> > > > > > > > the only node that seems to be doing all > >> the > >> >> > work > >> >> > >> is > >> >> > >> >>>> the > >> >> > >> >>>> > >> Master > >> >> > >> >>>> > >> > > > node. > >> >> > >> >>>> > >> > > > > > > > > >> >> > >> >>>> > >> > > > > > > > Does 15 nodes in a cluster increase the > >> >> network > >> >> > >> cost? > >> >> > >> >>>> What > >> >> > >> >>>> > >> can > >> >> > >> >>>> > >> > I > >> >> > >> >>>> > >> > > do > >> >> > >> >>>> > >> > > > > to > >> >> > >> >>>> > >> > > > > > > > setup > >> >> > >> >>>> > >> > > > > > > > the cluster to function more > efficiently? > >> >> > >> >>>> > >> > > > > > > > > >> >> > >> >>>> > >> > > > > > > > Thanks! > >> >> > >> >>>> > >> > > > > > > > Mithila Nagendra > >> >> > >> >>>> > >> > > > > > > > Arizona State University > >> >> > >> >>>> > >> > > > > > > > > >> >> > >> >>>> > >> > > > > > > > >> >> > >> >>>> > >> > > > > > > >> >> > >> >>>> > >> > > > > > >> >> > >> >>>> > >> > > > > >> >> > >> >>>> > >> > > > >> >> > >> >>>> > >> > > >> >> > >> >>>> > >> > >> >> > >> >>>> > > > >> >> > >> >>>> > > > >> >> > >> >>>> > > >> >> > >> >>>> > >> >> > >> >>> > >> >> > >> >>> > >> >> > >> >> > >> >> > >> > > >> >> > >> > >> >> > >> > >> >> > >> Ravi > >> >> > >> -- > >> >> > >> > >> >> > >> > >> >> > > > >> >> > > >> >> > >> >> > >> >> > >> >> -- > >> >> Alpha Chapters of my book on Hadoop are available > >> >> http://www.apress.com/book/view/9781430219422 > >> >> > >> > > >> > > >> > > > > > > > > -- > > Alpha Chapters of my book on Hadoop are available > > http://www.apress.com/book/view/9781430219422 > > > > > > -- > Alpha Chapters of my book on Hadoop are available > http://www.apress.com/book/view/9781430219422 >
