On Thu, May 10, 2012 at 9:33 AM, Todd Lipcon <t...@cloudera.com> wrote:
> That's real weird.. > > If you can reproduce this after a reboot, I'd recommend letting the DN > run for a minute, and then capturing a "jstack <pid of dn>" as well as > the output of "top -H -p <pid of dn> -b -n 5" and send it to the list. What I did after the reboot this morning was to move the my dn, nn, and mapred directories out of the the way, create a new one, formatted it, and restarted the node, it's now happy. I'll try moving the directories back later and do the jstack as you suggest. > > What JVM/JDK are you using? What OS version? > root@pl446:/# dpkg --get-selections | grep java java-common install libjaxp1.3-java install libjaxp1.3-java-gcj install libmysql-java install libxerces2-java install libxerces2-java-gcj install sun-java6-bin install sun-java6-javadb install sun-java6-jdk install sun-java6-jre install root@pl446:/# java -version java version "1.6.0_26" Java(TM) SE Runtime Environment (build 1.6.0_26-b03) Java HotSpot(TM) 64-Bit Server VM (build 20.1-b02, mixed mode) root@pl446:/# cat /etc/issue Debian GNU/Linux 6.0 \n \l > > -Todd > > > On Wed, May 9, 2012 at 11:57 PM, Darrell Taylor > <darrell.tay...@gmail.com> wrote: > > On Wed, May 9, 2012 at 10:52 PM, Raj Vishwanathan <rajv...@yahoo.com> > wrote: > > > >> The picture either too small or too pixelated for my eyes :-) > >> > > > > There should be a zoom option in the top right of the page that allows > you > > to view it full size > > > > > >> > >> Can you login to the box and send the output of top? If the system is > >> unresponsive, it has to be something more than an unbalanced hdfs > cluster, > >> methinks. > >> > > > > Sorry, I'm unable to login to the box, it's completely unresponsive. > > > > > >> > >> Raj > >> > >> > >> > >> >________________________________ > >> > From: Darrell Taylor <darrell.tay...@gmail.com> > >> >To: common-user@hadoop.apache.org; Raj Vishwanathan <rajv...@yahoo.com > > > >> >Sent: Wednesday, May 9, 2012 2:40 PM > >> >Subject: Re: High load on datanode startup > >> > > >> >On Wed, May 9, 2012 at 10:23 PM, Raj Vishwanathan <rajv...@yahoo.com> > >> wrote: > >> > > >> >> When you say 'load', what do you mean? CPU load or something else? > >> >> > >> > > >> >I mean in the unix sense of load average, i.e. top would show a load of > >> >(currently) 376. > >> > > >> >Looking at Ganglia stats for the box it's not CPU load as such, the > graphs > >> >shows actual CPU usage as 30%, but the number of running processes is > >> >simply growing in a linear manner - screen shot of ganglia page here : > >> > > >> > > >> > https://picasaweb.google.com/lh/photo/Q0uFSzyLiriDuDnvyRUikXVR0iWwMibMfH0upnTwi28?feat=directlink > >> > > >> > > >> > > >> >> > >> >> Raj > >> >> > >> >> > >> >> > >> >> >________________________________ > >> >> > From: Darrell Taylor <darrell.tay...@gmail.com> > >> >> >To: common-user@hadoop.apache.org > >> >> >Sent: Wednesday, May 9, 2012 9:52 AM > >> >> >Subject: High load on datanode startup > >> >> > > >> >> >Hi, > >> >> > > >> >> >I wonder if someone could give some pointers with a problem I'm > having? > >> >> > > >> >> >I have a 7 machine cluster setup for testing and we have been > pouring > >> data > >> >> >into it for a week without issue, have learnt several thing along > the > >> way > >> >> >and solved all the problems up to now by searching online, but now > I'm > >> >> >stuck. One of the data nodes decided to have a load of 70+ this > >> morning, > >> >> >stopping datanode and tasktracker brought it back to normal, but > every > >> >> time > >> >> >I start the datanode again the load shoots through the roof, and > all I > >> get > >> >> >in the logs is : > >> >> > > >> >> >STARTUP_MSG: Starting DataNode > >> >> > > >> >> > > >> >> >STARTUP_MSG: host = pl464/10.20.16.64 > >> >> > > >> >> > > >> >> >STARTUP_MSG: args = [] > >> >> > > >> >> > > >> >> >STARTUP_MSG: version = 0.20.2-cdh3u3 > >> >> > > >> >> > > >> >> >STARTUP_MSG: build = > >> >> > >> >> > >> > >file:///data/1/tmp/nightly_2012-03-20_13-13-48_3/hadoop-0.20-0.20.2+923.197-1~squeeze > >> >> >-************************************************************/ > >> >> > > >> >> > > >> >> >2012-05-09 16:12:05,925 INFO > >> >> >org.apache.hadoop.security.UserGroupInformation: JAAS Configuration > >> >> already > >> >> >set up for Hadoop, not re-installing. > >> >> > > >> >> >2012-05-09 16:12:06,139 INFO > >> >> >org.apache.hadoop.security.UserGroupInformation: JAAS Configuration > >> >> already > >> >> >set up for Hadoop, not re-installing. > >> >> > > >> >> >Nothing else. > >> >> > > >> >> >The load seems to max out only 1 of the CPUs, but the machine > becomes > >> >> >*very* unresponsive > >> >> > > >> >> >Anybody got any pointers of things I can try? > >> >> > > >> >> >Thanks > >> >> >Darrell. > >> >> > > >> >> > > >> >> > > >> >> > >> > > >> > > >> > > >> > > > > -- > Todd Lipcon > Software Engineer, Cloudera >
