在AWS Lambda中实现高效日志记录的最佳实践是使用Lambda提供的内置日志记录功能并结合使用云监控服务。以下是一些示例代码：

1. 在Python中使用内置日志记录：

import logging

def lambda_handler(event, context):
    logger = logging.getLogger(__name__)
    logger.setLevel(logging.INFO)

    # Log the input event
    logger.info('Received event: ' + json.dumps(event))

2. 将日志发送到云监控服务：

import boto3
import logging

def lambda_handler(event, context):
    logger = logging.getLogger(__name__)
    logger.setLevel(logging.INFO)
    
    # Create CloudWatch Logs client
    cloudwatch_logs = boto3.client('logs')
    
    # Log the input event
    logger.info('Received event: ' + json.dumps(event))
    
    # Send log messages to CloudWatch Logs
    cloudwatch_logs.create_log_group(logGroupName='/aws/lambda/my-function')
    cloudwatch_logs.create_log_stream(logGroupName='/aws/lambda/my-function', logStreamName=context.log_stream_name)
    cloudwatch_logs.put_log_events(logGroupName='/aws/lambda/my-function', logStreamName=context.log_stream_name, logEvents=[{'timestamp': int(time.time() * 1000), 'message': 'Sample log message.'}])