In the future, provide full dump using pastebin.com Write snippet of log in email.
Can you tell us what the following lines are about ? HBaseURLsDaysAggregator.java:124 HBaseURLsDaysAggregator.java:131 How many mappers were launched ? What value is used for hbase.zookeeper.property.maxClientCnxns ? You may need to increase the value for above setting. On Mon, Jul 4, 2011 at 9:26 AM, Lior Schachter <[email protected]> wrote: > I used kill -3, following the thread dump: > > ... > > > On Mon, Jul 4, 2011 at 6:22 PM, Ted Yu <[email protected]> wrote: > > > I wasn't clear in my previous email. > > It was not answer to why map tasks got stuck. > > TableInputFormatBase.getSplits() is being called already. > > > > Can you try getting jstack of one of the map tasks before task tracker > > kills > > it ? > > > > Thanks > > > > On Mon, Jul 4, 2011 at 8:15 AM, Lior Schachter <[email protected]> > > wrote: > > > > > 1. Currently every map gets one region. So I don't understand what > > > difference will it make using the splits. > > > 2. How should I use the TableInputFormatBase.getSplits() ? Could not > find > > > examples for that. > > > > > > Thanks, > > > Lior > > > > > > > > > On Mon, Jul 4, 2011 at 5:55 PM, Ted Yu <[email protected]> wrote: > > > > > > > For #2, see TableInputFormatBase.getSplits(): > > > > * Calculates the splits that will serve as input for the map tasks. > > The > > > > * number of splits matches the number of regions in a table. > > > > > > > > > > > > On Mon, Jul 4, 2011 at 7:37 AM, Lior Schachter <[email protected]> > > > > wrote: > > > > > > > > > 1. yes - I configure my job using this line: > > > > > TableMapReduceUtil.initTableMapperJob(HBaseConsts.URLS_TABLE_NAME, > > > scan, > > > > > ScanMapper.class, Text.class, MapWritable.class, job) > > > > > > > > > > which internally uses TableInputFormat.class > > > > > > > > > > 2. One split per region ? What do you mean ? How do I do that ? > > > > > > > > > > 3. hbase version 0.90.2 > > > > > > > > > > 4. no exceptions. the logs are very clean. > > > > > > > > > > > > > > > > > > > > On Mon, Jul 4, 2011 at 5:22 PM, Ted Yu <[email protected]> > wrote: > > > > > > > > > > > Do you use TableInputFormat ? > > > > > > To scan large number of rows, it would be better to produce one > > Split > > > > per > > > > > > region. > > > > > > > > > > > > What HBase version do you use ? > > > > > > Do you find any exception in master / region server logs around > the > > > > > moment > > > > > > of timeout ? > > > > > > > > > > > > Cheers > > > > > > > > > > > > On Mon, Jul 4, 2011 at 4:48 AM, Lior Schachter < > > [email protected]> > > > > > > wrote: > > > > > > > > > > > > > Hi all, > > > > > > > I'm running a scan using the M/R framework. > > > > > > > My table contains hundreds of millions of rows and I'm scanning > > > using > > > > > > > start/stop key about 50 million rows. > > > > > > > > > > > > > > The problem is that some map tasks get stuck and the task > manager > > > > kills > > > > > > > these maps after 600 seconds. When retrying the task everything > > > works > > > > > > fine > > > > > > > (sometimes). > > > > > > > > > > > > > > To verify that the problem is in hbase (and not in the map > code) > > I > > > > > > removed > > > > > > > all the code from my map function, so it looks like this: > > > > > > > public void map(ImmutableBytesWritable key, Result value, > Context > > > > > > context) > > > > > > > throws IOException, InterruptedException { > > > > > > > } > > > > > > > > > > > > > > Also, when the map got stuck on a region, I tried to scan this > > > region > > > > > > > (using > > > > > > > simple scan from a Java main) and it worked fine. > > > > > > > > > > > > > > Any ideas ? > > > > > > > > > > > > > > Thanks, > > > > > > > Lior > > > > > > > > > > > > > > > > > > > > > > > > > > > >
