ERROR-org.postgresql.util.PSQLException: An I/O error occurred while sending to the backend.

Hi,
I am facing 'org.postgresql.util.PSQLException: An I/O error occurred while
sending to the backend' error while performing jdbc batch insert in postgre
sql database using proxool connection pool. This error is random, but once
it starts to come, it comes very frequently.
Both my database server and my jetty server are on same linux machine and
the batch size is 1000, but changing batch size doesn't eliminate the error.
I don't have much idea about firewall but I don't think it should be an
issue on same machine.

Setup details:-
pgsql 9.3
pg-jdbc driver - 9.3
proxool for jdbc connection pooling

Stack trace:-
unknown-ERROR-[JdbcExporter] Error while executing batch : Batch entry 0
insert into ldev
(array_serial,date_time,ldev,read_iops,write_iops,rand_iops,seq_iops,read_xfer,write_xfer,read_hit_pct,write_hit_pct,read_resp,write_resp,total_resp,rand_xfer,seq_xfer)
values (cast(get_SerialNo('48015') as integer),'2015-04-28 00:00:00.000000
+00:00:00',get_funcNameFromSignature('48015-00:00:CD'),3.1166666666666667,0.3833333333333333,(COALESCE(2.1166666666666667,0)+COALESCE(0.3833333333333333,0)),(COALESCE(1.0,0)+COALESCE(0.0,0)),convert_KBToMB(3078.483333333333),convert_KBToMB(6.383333333333334),100.0,NULL,convert_MiliSecToMicroSec(3.105),convert_MiliSecToMicroSec(0.2816666666666666),convert_MiliSecToMicroSec(3.386666666666666),convert_KBToMB(0.0),convert_KBToMB(0.0))
was aborted. Call getNextException to see the cause.
2015-06-01 06:06:37,436 [48015_vsp_LdevPerf_12387041536606161 9364]
unknown-ERROR-Batch Execute failed while inserting in database.
2015-06-01 06:06:37,436 [48015_vsp_LdevPerf_12387041536606161 9364]
unknown-ERROR-org.postgresql.util.PSQLException: An I/O error occurred
while sending to the backend.
at
org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:411)
at
org.postgresql.jdbc2.AbstractJdbc2Statement.executeBatch(AbstractJdbc2Statement.java:2889)
at sun.reflect.GeneratedMethodAccessor67.invoke(Unknown Source)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at
org.logicalcobwebs.proxool.ProxyStatement.invoke(ProxyStatement.java:68)
at
org.logicalcobwebs.cglib.proxy.Proxy$ProxyImpl$$EnhancerByCGLIB$$44f8dff2.executeBatch(<generated>)
at com.cs.core.tasks.export.JdbcExporter.a(JdbcExporter.java:393)
at com.cs.core.tasks.export.JdbcExporter.e(JdbcExporter.java:345)
at Aaaa_bf.c(BaseDataProcessor.java:137)
at Aaaa_bi.a(DataProcessManager.java:114)
at Aaaa_bi.b(DataProcessManager.java:29)
at Aaaa_op.b(TaskScheduler.java:255)
at Aaaa_ok.tj(TaskProcessInitiator.java:25)
at Aaaa_ok.call(TaskProcessInitiator.java:11)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.SocketException: Socket closed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:152)
at java.net.SocketInputStream.read(SocketInputStream.java:122)
at
org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:143)
at
org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:112)
at
org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:71)
at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:269)
at
org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1704)
at
org.postgresql.core.v3.QueryExecutorImpl.sendQuery(QueryExecutorImpl.java:1093)
at
org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:396)
... 20 more

Please help me with this.