Hi,
   Every time I restart the cassandra server, the cpu usage continue to be very high(98%) for days. But I have no reading or writing to this server.
I have tried the follow cmd:

date; date `date +"%m%d%H%M%C%y.%S"`; date;

It doesn't work.

The tail of system.log:
DEBUG [Thrift:1701] 2013-03-20 00:01:14,229 CustomTThreadPoolServer.java (line 209) Thrift transport error occurred during processing of message.
org.apache.thrift.transport.TTransportException: java.net.SocketException: Broken pipe
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:161)
at org.apache.thrift.transport.TFramedTransport.flush(TFramedTransport.java:158)
at org.apache.thrift.ProcessFunction.process(ProcessFunction.java:36)
at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:34)
at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:199)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:65)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:123)
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:159)
... 7 more
DEBUG [Thrift:2212] 2013-03-20 00:01:14,217 CassandraServer.java (line 341) multiget_slice
DEBUG [Thrift:2380] 2013-03-20 00:01:14,212 CustomTThreadPoolServer.java (line 209) Thrift transport error occurred during processing of message.
org.apache.thrift.transport.TTransportException: java.net.SocketException: Broken pipe
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:161)
at org.apache.thrift.transport.TFramedTransport.flush(TFramedTransport.java:158)
at org.apache.thrift.ProcessFunction.process(ProcessFunction.java:36)
at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:34)
at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:199)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:65)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:123)
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:159)
... 7 more
DEBUG [Thrift:2379] 2013-03-20 00:01:14,207 CustomTThreadPoolServer.java (line 209) Thrift transport error occurred during processing of message.
org.apache.thrift.transport.TTransportException: java.net.SocketException: Broken pipe
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:161)
at org.apache.thrift.transport.TFramedTransport.flush(TFramedTransport.java:158)
at org.apache.thrift.ProcessFunction.process(ProcessFunction.java:36)
at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:34)
at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:199)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:65)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:123)
at org.apache.thrift.transport.TIOStreamTransport.flush(TIOStreamTransport.java:159)
... 7 more


If you known anything about it, please help me.


Thanks,

China.