new ExpressRunner() 导致内存泄漏

[picksta]

线上使用时发现执行ql表达式会产生较严重的内存泄漏，老年代一直增长。原因是每次执行都new一次ExpressRunner()，改成全局变量就好了。请问问为什么新建ExpressRunner会出现内存泄漏。

简单demo：
public class ExpressMain {

public static ExpressRunner runner = new ExpressRunner();

public static void demo1() throws Exception {
    ExpressRunner runner = new ExpressRunner();
    runner.setIgnoreConstChar(true);
    DefaultContext<String, Object> context = new DefaultContext<String, Object>();
    context.put("package_order_cnt_json","234");
    context.put("finishOrderDiscountRate",80);
    context.put("c",3);
    String express = " (package_order_cnt_json!= null  and  (package_order_cnt_json like '%269%' or package_order_cnt_json like '%234%' or package_order_cnt_json like '%111%' or package_order_cnt_json like '%333%' or package_order_cnt_json like '%22%' or package_order_cnt_json like '%5564%' or package_order_cnt_json like '%43%'))\n";
    Object execute = runner.execute(express, context, null, true, false);
    System.out.println(execute);
}


public static void main(String[] args) throws Exception {
    while (true) {
        demo1();
    }

}

}

[baoxingjie]

本来就应该是用单例模式

…

---- 回复的原邮件 ---- | 发件人 | ***@***.***> | | 发送日期 | 2024年01月30日 16:23 | | 收件人 | alibaba/QLExpress ***@***.***> | | 抄送人 | Subscribed ***@***.***> | | 主题 | [alibaba/QLExpress] new ExpressRunner() 导致内存泄漏 (Issue #312) | 线上使用时发现执行ql表达式会产生较严重的内存泄漏，老年代一直增长。原因是每次执行都new一次ExpressRunner()，改成全局变量就好了。请问问为什么新建ExpressRunner会出现内存泄漏。 简单demo： public class ExpressMain { public static ExpressRunner runner = new ExpressRunner(); public static void demo1() throws Exception { ExpressRunner runner = new ExpressRunner(); runner.setIgnoreConstChar(true); DefaultContext<String, Object> context = new DefaultContext<String, Object>(); context.put("package_order_cnt_json","234"); context.put("finishOrderDiscountRate",80); context.put("c",3); String express = " (package_order_cnt_json!= null and (package_order_cnt_json like '%269%' or package_order_cnt_json like '%234%' or package_order_cnt_json like '%111%' or package_order_cnt_json like '%333%' or package_order_cnt_json like '%22%' or package_order_cnt_json like '%5564%' or package_order_cnt_json like '%43%'))\n"; Object execute = runner.execute(express, context, null, true, false); System.out.println(execute); } public static void main(String[] args) throws Exception { while (true) { demo1(); } } } image.png (view on web) — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[cying314]

那需要并行计算多组表达式，但各组间包含不同宏定义、操作符的情况怎么解决？

宏定义不能像上下文那样在执行表达式时传入，必须设置在runner上。

并且这些宏定义分组还是由决策平台客户端决定的，不能初始化为固定数量的runner单例。

如果以分组粒度去动态创建runner的话，又会出现题主所说的内存泄漏问题。

[MoonNigth]

版本：3.3.2
跑了五个小时，没有发现明显的内存增加

    @Test
    public  void testWhile() throws Exception {
        while (true) {
            ExpressRunner runner = new ExpressRunner();
            runner.setIgnoreConstChar(true);
            DefaultContext<String, Object> context = new DefaultContext<String, Object>();
            context.put("package_order_cnt_json","234");
            context.put("finishOrderDiscountRate",80);
            context.put("c",3);
            String express = " (package_order_cnt_json!= null  and  (package_order_cnt_json like '%269%' or package_order_cnt_json like '%234%' or package_order_cnt_json like '%111%' or package_order_cnt_json like '%333%' or package_order_cnt_json like '%22%' or package_order_cnt_json like '%5564%' or package_order_cnt_json like '%43%'))\n";
            Object execute = runner.execute(express, context, null, true, false);
            System.out.println(execute);
        }
    }

[bbenguo]

runner.execute(express, context, null, true, false);

你这个用例，倒数第二个参数应该填false， 或者执行完毕后执行一下这个 runner.clearExpressCache()