Thanks for digging in on this one. Let us know how your -Djava.net.preferIPv4Stack=true goes. I'd like to add below to FAQ. St.Ack
On Thu, May 28, 2009 at 1:58 PM, gcr44 <geoffry.robe...@gmail.com> wrote: > > It says to disable ipv6 in the document: "Running Hadoop On Ubuntu Linux". > > > http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_(Single-Node_Cluster)<http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Single-Node_Cluster%29> > > > Parent Message unknown Warning on turning on ipv6 on your Hadoop clusters > Click to flag this post > > by Runping Qi Dec 17, 2008; 04:15pm :: Rate this Message: - Use ratings to > moderate (?) > > Reply | Reply to Author | Print | View Threaded | Show Only this Message > > > If you may have turned on ipv6 on your hadoop cluster, it may cause severe > performance hit! > > When I ran the gridmix2 benchmark on a newly constructed cluster, it took > 30% more time than the baseline time that was obtained on a similar > cluster. > > I noticed that some task processes on some machines took 3+ minutes to > initialize. > After examining these processes in details, I found that they were stuck at > socket initialization tile, as shown in the following stack: > > "main" prio=10 tid=0x0805b400 nid=0x4681 runnable [0xf7fbb000..0xf7fbc208] > java.lang.Thread.State: RUNNABLE > at java.net.PlainSocketImpl.initProto(Native Method) > at java.net.PlainSocketImpl.<clinit>(PlainSocketImpl.java:84) > at java.net.Socket.setImpl(Socket.java:434) > at java.net.Socket.<init>(Socket.java:68) > at sun.nio.ch.SocketAdaptor.<init>(SocketAdaptor.java:50) > at sun.nio.ch.SocketAdaptor.create(SocketAdaptor.java:55) > at sun.nio.ch.SocketChannelImpl.socket(SocketChannelImpl.java:105) > - locked <0xf17a38c8> (a java.lang.Object) > at > > org.apache.hadoop.net.StandardSocketFactory.createSocket(StandardSocketFacto > ry.java:58) > at > org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:298) > - locked <0xf1795db0> (a org.apache.hadoop.ipc.Client$Connection) > at org.apache.hadoop.ipc.Client$Connection.access$1700(Client.java:178) > at org.apache.hadoop.ipc.Client.getConnection(Client.java:820) > at org.apache.hadoop.ipc.Client.call(Client.java:705) > at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:216) > at org.apache.hadoop.mapred.$Proxy0.getProtocolVersion(Unknown Source) > at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:348) > at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:335) > at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:372) > at > org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2188) > > > I did a search on the web and found that that was due to a known bug for > Java related to ipv6. > > More information about the bug can be found at the following two pages: > > http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6483406 > http://edocs.bea.com/jrockit/releases/5026x/relnotes/relnotes.html > > {quote} > Slow startup because of a hang in java.net.PlainSocketImpl.initProto(), > which typically is called when creating the first Socket or > ServerSocket. > In BEA JRockit 5.0 R26 the network stack is configured so that IPv6 is > used in preference to IPv4 when it is present. > During initialization of the network stack, the network code connects a > socket to its own loopback interface to set up some data structures. > Blocking this connection (e.g. with a firewall) will cause the > initialization code to wait for a socket timeout, after which the system > falls back on using IPv4. > > > {quote} > > Suggested Workaround: > > Either set -Djava.net.preferIPv4Stack=true for the child process option, > which forces Java to use IPv4 > instead, or you disable IPv6 entirely in the system. The proper fix is to > allow IPv6 traffic from localhost to localhost. > For more information, see the Sun documentation: > http://java.sun.com/j2se/1.4.2/docs/guide/net/ipv6_guide/#ipv6-networking > > I just found the following workaround, which I shall give a try. > > -Djava.net.preferIPv4Stack=true > > > stack-3 wrote: > > > > On Thu, May 28, 2009 at 12:31 PM, gcr44 <geoffry.robe...@gmail.com> > wrote: > > > >> > >> All, > >> > >> After some digging, I have come to this: According to my System > >> Administrator, the HBASE installation guide calls for ipv6 to be > >> disabled. > > > > > > That seems a little silly. We need to fix that if its true. Where in > the > > doc. does it say that? > > Thanks, > > St.Ack > > > > > > -- > View this message in context: > http://www.nabble.com/HBASE-Connection-Refused%3A-no-further-information-tp23733471p23769993.html > Sent from the HBase User mailing list archive at Nabble.com. > >
