Hi, thanks for reply!
> What should we add here to make the doc more clear on BufferedMutator? > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/BufferedMutator.html It's pretty clear. > And in the example? Example shows that both connection and buffered mutator are thread safe and they are closed at once. - Should keep single instance of connection and bufferedmutator per thread? - Should I keep connection per thread and instantiate mutator for each request? - what happens if autoflush enabled? - is it possible to turn on sync mode for saving data? - Connection could get into failed/invalid state for some reason (RS down, RS up, some networking partitioned happend). Is it possible? If it's possible, then what is the right way to handle it: "close" failed connection and ask for new one? > I assume users is collection of User's. > Have you tried obtaining / closing mutator for each User instead of sharing > the mutator ? > If another flush, say because there were lots of puts, then when close > comes in, we are out of threads and you'd get below. Looks like it's the root cause, let me try! Thank you for detailed explanation! 2016-02-09 7:10 GMT+01:00 Stack <st...@duboce.net>: > On Mon, Feb 8, 2016 at 3:01 PM, Serega Sheypak <serega.shey...@gmail.com> > wrote: > > > Hi, I'm confused with new HBase 1.0 API. API says that application should > > manage connections (Previously HConnections) on their own. Nothing is > > managed itnernally now. > > > > > That is right. > > > > > > Here is an example: > > > > > https://hbase.apache.org/xref/org/apache/hadoop/hbase/client/example/BufferedMutatorExample.html > > > > It gives no clue about lifecycle :( > > > > > Connection is fairly explicit: > > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Connection.html > > What should we add here to make the doc more clear on BufferedMutator? > > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/BufferedMutator.html > > And in the example? > > > > > Right now I create single connection instance for servlet and > > BufferedMutator per request. > > > > > > > The recommendation is a singled BufferedMutator shared across requests. > > > > > > //getConnection returns single instance, it doesn't return new connection > > each time > > def mutator = > > getConnection().getBufferedMutator(getBufferedMutatorParams()) > > > > > getConnection is your method? > > > getBufferedMutator creates a new one? > > > > > users.each{ mutator.mutate(toPut(it))} > > mutator.close() //exception is thrown here > > > > > The close is flushing out all the writes. > > If a BufferedMutator per servlet instance, there are probably many when > many requests coming in. > > See what happens when you create one: > > > http://hbase.apache.org/xref/org/apache/hadoop/hbase/client/ConnectionImplementation.html#313 > > which calls through to here.... > > http://hbase.apache.org/xref/org/apache/hadoop/hbase/client/HTable.html#126 > > ... which creates an executor of max 1 task only. > > If another flush, say because there were lots of puts, then when close > comes in, we are out of threads and you'd get below. > > St.Ack > > > > > > > > And I get tons of exceptions thrown on "mutator.close()", what do I do > > wrong? > > > > WARNING: #905, the task was rejected by the pool. This is unexpected. > > Server is node04.server.com, 60020,1447338864601 > > java.util.concurrent.RejectedExecutionException: Task > > java.util.concurrent.FutureTask@5cff3b40 rejected from > > java.util.concurrent.ThreadPoolExecutor@686c2853[Terminated, pool size = > > 0, > > active threads = 0, queued tasks = 0, completed tasks = 1] > > at > > > > > java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2047) > > at > > > java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:823) > > at > > > > > java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1369) > > at > > > > > java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:112) > > at > > > > > org.apache.hadoop.hbase.client.AsyncProcess$AsyncRequestFutureImpl.sendMultiAction(AsyncProcess.java:956) > > at > > > > > org.apache.hadoop.hbase.client.AsyncProcess$AsyncRequestFutureImpl.access$000(AsyncProcess.java:574) > > at > > > > > org.apache.hadoop.hbase.client.AsyncProcess.submitMultiActions(AsyncProcess.java:423) > > at > > org.apache.hadoop.hbase.client.AsyncProcess.submit(AsyncProcess.java:403) > > at > > org.apache.hadoop.hbase.client.AsyncProcess.submit(AsyncProcess.java:320) > > at > > > > > org.apache.hadoop.hbase.client.BufferedMutatorImpl.backgroundFlushCommits(BufferedMutatorImpl.java:206) > > at > > > > > org.apache.hadoop.hbase.client.BufferedMutatorImpl.close(BufferedMutatorImpl.java:158) > > at org.apache.hadoop.hbase.client.BufferedMutator$close$0.call(Unknown > > Source) > > >
