On Mon, Feb 29, 2016 at 10:26 AM, z11373 <[email protected]> wrote: > Hi Keith, > Yes, T=1 was calling createScanner, and yes, my current code does create > single scanner per thread, but I already have new code does use > BatchScanner. > > For T=4, it's another thread, but I believe it was spawned from thread > 0x1f46, there are many of this stack, and I just noticed few of them have > this stack: > > "pool-3-thread-1277" #7656 prio=5 os_prio=0 tid=0x00007fee9408e000 > nid=0x2033 waiting for monitor entry [0x00007fef9f0f1000] > java.lang.Thread.State: BLOCKED (on object monitor) > at > > org.apache.accumulo.core.client.impl.TabletLocator.getLocator(TabletLocator.java:101) > - waiting to lock <0x000000068032c130> (a java.lang.Class for > org.apache.accumulo.core.client.impl.TabletLocator) > at > > org.apache.accumulo.core.client.impl.ThriftScanner.scan(ThriftScanner.java:228) > at > > org.apache.accumulo.core.client.impl.ScannerIterator$Reader.run(ScannerIterator.java:84) > at > > org.apache.accumulo.core.client.impl.ScannerIterator.hasNext(ScannerIterator.java:177) > ... > > That 'BLOCKED' state seems suspicious to me. >
Its waiting to lock 0x000000068032c130, would be nice to see what thread has 0x000000068032c130 locked and what that thread is doing. > > For T=5, the high level thread was calling scanner iterator's hasNext() > > Do you know why reading via this connector would take > 8s, while on new > connector (in same process), the read would mostly only take < 0.1s (see > that huge difference)? > I don't know. One guess is that the connector was created w/ older/different config (like list of zookeepers) and something has to timeout (like a connection to non-existant zookeeper) before it makes progress. Note, the tablet locator (cache of tablet locations) is a static resource shared among all connectors created in same classloader. > > Thanks, > Z > > > > > -- > View this message in context: > http://apache-accumulo.1065345.n5.nabble.com/cached-connector-tp16202p16262.html > Sent from the Developers mailing list archive at Nabble.com. >
