Hi All, In our cluster region server logs are filled with response too slow message. This is causing jobs to slow down. How can I debug what is the reason for this slowness.
We have enabled short circuit reads and region server has 27GB RAM. Here is a trace when regionserver starts. Thu Aug 14 20:23:51 GMT 2014 Starting regionserver on nodex core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 966365 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 32768 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 10240 cpu time (seconds, -t) unlimited max user processes (-u) 966365 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited 2014-08-14 20:23:53,341 WARN org.apache.hadoop.conf.Configuration: fs.default.name is deprecated. Instead, use fs.defaultFS 2014-08-14 20:23:53,342 WARN org.apache.hadoop.conf.Configuration: mapred.task.id is deprecated. Instead, use mapreduce.task.attempt.id 2014-08-14 20:23:53,884 WARN org.apache.hadoop.conf.Configuration: slave.host.name is deprecated. Instead, use mapreduce.tasktracker.host.name 2014-08-14 20:24:03,999 WARN org.apache.hadoop.conf.Configuration: hadoop.native.lib is deprecated. Instead, use io.native.lib.available 2014-08-14 20:26:47,605 ERROR org.apache.hadoop.hbase.regionserver.metrics.SchemaMetrics: Inconsistent configuration. Previous configuration for using table name in metrics: true, new configuration: false 2014-08-14 20:28:23,491 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":18725,"call":"next(-8041903839443097981, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.248:58716 ","starttimems":1408048084720,"queuetimems":0,"class":"HRegionServer","responsesize":5031595,"method":"next"} 2014-08-14 21:35:16,740 WARN org.apache.hadoop.hbase.util.Sleeper: We slept 14912ms instead of 3000ms, this is likely due to a long garbage collecting pause and it's usually bad, see http://hbase.apache.org/book.html#trouble.rs.runtime.zkexpired 2014-08-14 21:42:28,477 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":16968,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:36657 ","starttimems":1408052531504,"queuetimems":0,"class":"HRegionServer","responsesize":1959532,"method":"next"} 2014-08-14 21:42:56,923 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":10591,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:40818 ","starttimems":1408052566327,"queuetimems":1,"class":"HRegionServer","responsesize":2987578,"method":"next"} 2014-08-14 21:44:24,372 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":10656,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:41993 ","starttimems":1408052653710,"queuetimems":1,"class":"HRegionServer","responsesize":3039779,"method":"next"} 2014-08-14 21:45:50,598 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":12418,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:45197 ","starttimems":1408052738174,"queuetimems":10,"class":"HRegionServer","responsesize":2476903,"method":"next"} 2014-08-14 21:46:15,187 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":23766,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:49425 ","starttimems":1408052751414,"queuetimems":0,"class":"HRegionServer","responsesize":5681175,"method":"next"} 2014-08-14 21:47:09,041 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":12320,"call":"next(5487686201525374976, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.249:50269 ","starttimems":1408052816698,"queuetimems":1,"class":"HRegionServer","responsesize":2986949,"method":"next"} 2014-08-14 21:49:23,833 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":11389,"call":"next(1227841280814011139, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.122:41976 ","starttimems":1408052952415,"queuetimems":0,"class":"HRegionServer","responsesize":3160025,"method":"next"} 2014-08-14 21:49:23,869 WARN org.apache.hadoop.ipc.HBaseServer: Exception while changing ops : java.nio.channels.CancelledKeyException 2014-08-14 21:49:23,900 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":11428,"call":"next(9103372947568217267, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.41:35241 ","starttimems":1408052952469,"queuetimems":0,"class":"HRegionServer","responsesize":1809158,"method":"next"} 2014-08-14 21:49:23,902 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":11415,"call":"next(-3120240140302998196, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.195:46046 ","starttimems":1408052952468,"queuetimems":0,"class":"HRegionServer","responsesize":1826929,"method":"next"} 2014-08-14 21:49:24,050 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":11438,"call":"next(3799907609071248384, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":" 17.170.176.154:42797 ","starttimems":1408052952459,"queuetimems":0,"class":"HRegionServer","responsesize":2628568,"method":"next"} 2014-08-14 21:49:24,057 WARN org.apache.hadoop.ipc.HBaseServer: (responseTooSlow): {"processingtimems":11843,"call":"next(-1679362783893333095, 10), rpc version=1, client version=29, methodsFingerPrint=-1368823753","client":"17.170 Thanks, Rahul