Java Tomcat PostgreSQL 「バックエンドへの送信中に、入出力エラーが起こりました。」について

2020-12-21 14:19:06:928,重大,org.postgresql.util.PSQLException: バックエンドへの送信中に、入出力エラーが起こりました。
    at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:350)
    at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:473)
    at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:393)
    at org.postgresql.jdbc.PgPreparedStatement.executeWithFlags(PgPreparedStatement.java:164)
    at org.postgresql.jdbc.PgPreparedStatement.executeQuery(PgPreparedStatement.java:114)
    ...
Caused by: java.io.EOFException
    at org.postgresql.core.PGStream.receiveChar(PGStream.java:443)
    at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2057)
    at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:323)
    ... 12 more

2020-12-21 14:19:06:975,普通,コネクションを検証しています 
org.postgresql.util.PSQLException: このコネクションは既にクローズされています。
    at org.postgresql.jdbc.PgConnection.checkClosed(PgConnection.java:885)
    at org.postgresql.jdbc.PgConnection.setNetworkTimeout(PgConnection.java:1610)
    at org.postgresql.jdbc.PgConnection.isValid(PgConnection.java:1436)
    at org.apache.commons.dbcp2.DelegatingConnection.isValid(DelegatingConnection.java:897)
    at org.apache.commons.dbcp2.PoolableConnection.validate(PoolableConnection.java:270)
    at org.apache.commons.dbcp2.PoolableConnectionFactory.validateConnection(PoolableConnectionFactory.java:630)
    at org.apache.commons.dbcp2.PoolableConnectionFactory.validateObject(PoolableConnectionFactory.java:648)
    at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:492)
    at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:363)
    at org.apache.commons.dbcp2.PoolingDataSource.getConnection(PoolingDataSource.java:134)
    at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:753)
    ...

LOG: could not send data to client: Broken pipe
STATEMENT: {実行SQL}
FATAL: connection to client lost
STATEMENT: {実行SQL}
LOG: database system was interrupted; last known up at 2020-12-21 13:10:24 UTC
LOG: database system was not properly shut down; automatic recovery in progress
LOG: record with zero length at 60/66A6D1D0
LOG: redo is not required
LOG: MultiXact member wraparound protections are now enabled
LOG: database system is ready to accept connections
LOG: autovacuum launcher started
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet
LOG: incomplete startup packet

private Connection getConnection() throws SQLException {
    Connection connection = DriverManager.getConnection(url);
    return connection;
}

private Object query() {
    try (Connection connection = getConnection();
            PreparedStatement preparedST = connection.prepareStatement(sql);) {
        /*パラメータの設定*/
        preparedST.setLong(1, param);
        ...
        /* クエリーの実行 */
        try (ResultSet rs = preparedST.executeQuery()) {
            /* Result Set から値を取得する */
            ...
        }
    }
}

package main;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Date;

public class Sample {

    static {
        try {
            Class.forName("org.postgresql.Driver");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) throws Exception {
        System.out.print("START,");
        System.out.println(new Date());
        String url = "jdbc:postgresql://192.168.3.2:5432/sample?currentSchema=user1";
        String user = "user";
        String password = "password";
        String sql = "select pg_sleep(600);";
        try (Connection conn = DriverManager.getConnection(url, user, password);
                PreparedStatement pstmt = conn.prepareStatement(sql);) {
            try (ResultSet rs = pstmt.executeQuery();) {
                System.out.print("OK,");
                System.out.println(new Date());
            }
        } catch (Exception e) {
            System.out.print("ERROR,");
            System.out.println(new Date());
            e.printStackTrace();
        }
        System.out.print("END,");
        System.out.println(new Date());
    }
}

WITH q1 AS (
    SELECT
        *
    FROM
        public.table1 AS t1
    WHERE
        ...
),
q2 AS (
    SELECT
        *
    FROM
        public.table2 AS t2
    WHERE
        (id) IN (
            SELECT DISTINCT
                id
            FROM
                q1
        )
),
q3 AS (
    SELECT
        *
    FROM
        public.table3 AS t3
    WHERE
        ...
)
SELECT DISTINCT
    COUNT(*)
FROM
    q1 AS t1,
    q2 AS t2,
    q3 AS t3
WHERE
    t1.id = t2.id
    AND t2.code = t3.code
    ...