为什么Google Cloud SQL(使用JDBC)比从我的个人计算机上插入Google App Engine的记录需

Question

i可以在3.5秒内从我的计算机中插入2000记录，GAE需要14.0秒才能做同一件事。我看不到如何让Google驱动程序使用RewriteBatchedStatements设置。

这是我相关的Java代码：

package year2016.tax8949.database2;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;
import java.util.Properties;
import java.util.logging.Logger;
public class Form89492016TableInserter {
private static final Logger log 
    = Logger.getLogger( "Form89492016TableInserter" );
protected static final String USERNAME = "xxxx";
protected static final String PASSWORD = "xxxxx";
protected static final String INSTANCE_CONNECTION_NAME 
    = "xxxx:us-central1:xxxxx";
protected static final String DB_NAME = "xxxxxx";
protected static final String IP_ADDRESS = "xxx.1xx.2xx.4x";
protected static final String SQL_INSERT 
    = "INSERT into Forms1099B ( orderNumber,acctId,qty,secDesc,dateAcq,dateSold,salesPrice,cost,basisAdj,washAdj,nomineeAdj,otherAdj,term,basisRep,rep1099B,tranType,dateAcqVar,covered,symbol,expired ) VALUES ( ?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,? )";

// Whether connecting from Google App Engine
private boolean fromGAE = false;
// JDBC connection
private Connection conn = null;
public Form89492016TableInserter( boolean fromGAE ) {
    this.fromGAE = fromGAE;
}
public void insertBatch( List<Forms1099BRecordBean> records ) {
    int batchSize = 500;
    insertBatchUsingSize( records, batchSize );
}
public void insertBatchUsingSize( List<Forms1099BRecordBean> records, 
                                  int batchSize ) {
    try {
        initializeConnection( );
        doInsertions( records, batchSize );
        closeConnection( );
    }
    catch( SQLException e ) {
        log.severe( e.getMessage( ) );
    }
}
public void closeConnection( ) throws SQLException {
    if ( conn != null ) { 
        conn.close( ); 
    } 
}
public void initializeConnection( ) throws SQLException {
    String driverName 
        = ( fromGAE ) ? "com.mysql.jdbc.GoogleDriver" : 
                        "com.mysql.jdbc.Driver";
    try {
        Class.forName( driverName );
    }
    catch( ClassNotFoundException e ) {
        log.severe( e.getMessage( ) );
        return;
    }
    if ( fromGAE ) {
        String connectionString 
            = String.format( 
                 "jdbc:google:mysql://%s/%s?user=root&password=%s", 
                 INSTANCE_CONNECTION_NAME, 
                 DB_NAME, 
                 PASSWORD );
        conn = DriverManager.getConnection( connectionString );
    }
    else {
        String url = String.format( "jdbc:mysql://%s:3306/%s",
                                    IP_ADDRESS,
                                    DB_NAME );
        Properties props = new Properties();
        props.setProperty( "user", USERNAME );
        props.setProperty( "password", PASSWORD );
        props.setProperty( "rewriteBatchedStatements", "true" );
        conn = DriverManager.getConnection( url, props );    
    }
}
private void doInsertions( List<Forms1099BRecordBean> records,
                           int batchSize ) throws SQLException {
    try ( PreparedStatement stmt = conn.prepareStatement( SQL_INSERT ) ) {
        for (int i = 0; i < records.size( ); i++) {
            Forms1099BRecordBean item = records.get( i );
            stmt.setString( 1, item.getOrderNumber() ); 
            stmt.setString( 2, item.getAcctId() ); 
            stmt.setString( 3, item.getQty() ); 
            stmt.setString( 4, item.getSecDesc() ); 
            stmt.setDate( 5, item.getDateAcq() ); 
            stmt.setDate( 6, item.getDateSold() ); 
            stmt.setBigDecimal( 7, item.getSalesPrice() ); 
            stmt.setBigDecimal( 8, item.getCost() ); 
            stmt.setBigDecimal( 9, item.getBasisAdj() ); 
            stmt.setBigDecimal( 10, item.getWashAdj() ); 
            stmt.setBigDecimal( 11, item.getNomineeAdj() ); 
            stmt.setBigDecimal( 12, item.getOtherAdj() ); 
            stmt.setString( 13, item.getTerm() ); 
            stmt.setString( 14, item.getBasisRep() ); 
            stmt.setString( 15, item.getRep1099B() ); 
            stmt.setString( 16, item.getTranType() ); 
            stmt.setString( 17, item.getDateAcqVar() ); 
            stmt.setString( 18, item.getCovered() ); 
            stmt.setString( 19, item.getSymbol() ); 
            stmt.setString( 20, item.getExpired() ); 
            stmt.addBatch( );
            // Execute every N items.
            if ( (i + 1) % batchSize == 0 ) {
                stmt.executeBatch( );     
            }
        }
        stmt.executeBatch( );
    }
}
}

Answer 1

通常，将本地计算机上的性能与GAE上的性能进行比较，因为它不是苹果与苹果的比较：

• 如今，大多数本地机器都比GAE实例机器强大得多
• 本地机器可能正在运行与GAE不同的操作系统（如果这意味着更快或较慢）
• 本地机器通常在裸机平台上运行OS，GAE实例在容器或VMS上运行
• SDK只是GAE Infra代码功能的（一部分）的模拟器，而不是实际 GAE Infra Code
• 大多数（如果不是全部）GAE服务实际上并未在您的应用程序实例上运行，而是通过RPC访问；内部GAE网络非常快，但仍比当量的SDK效仿要慢得多，该仿真全部是本地机器的内部