Question

gwan版本：3.12.26

servlet类型：C和Perl

问题：

gwan内部缓存请求不重新读取脚本

试验：

创建'log'目录：

[bash]# mkdir -p /dev/shm/random-c
[bash]# chmod 777 /dev/shm/random-c

create /path/to/gwan/0.0.0.0_8080/#0.0.0.0/csp/random.c

// ============================================================================
// C servlet sample for the G-WAN Web Application Server (http://trustleap.ch/)
// ----------------------------------------------------------------------------
// hello.c: just used with Lighty's Weighttp to benchmark a minimalist servlet
// ============================================================================
// imported functions:
//   get_reply(): get a pointer on the 'reply' dynamic buffer from the server
//    xbuf_cat(): like strcat(), but it works in the specified dynamic buffer
// ----------------------------------------------------------------------------
#include <sys/time.h>
#include "gwan.h" // G-WAN exported functions
#include <stdio.h>
#include <stdlib.h>
#include <string.h>


//------------------
void init_random(){
    struct /*sys/time.h->*/timeval res;
    /*sys/time.h->*/gettimeofday(&res,NULL);
   /*stdlib.h->*/srand( (unsigned int)/*stdlib.h->*/time(NULL) + res.tv_usec);
}

//------------------
char *get_rnd_char(int num){
    char *char_list = "1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
    int  char_list_len = 62;
    char *ret = (char *)/*stdlib.h->*/malloc((num * sizeof(char)) + 1);
    int i,r;


    for(i=0;i<num;i++){
        r=(int) (/*stdlib.h->*/rand() % char_list_len);
        ret[i] = char_list[r==char_list_len ? r-1 : r];
    }
    ret[num] = '\0';
    return ret;
}

//------------------
int main(int argc, char *argv[])
{
    char *rnd_out; //-- random data for browser output and file input
    char *rnd_file; //-- random file
    char *rnd_path; //-- for speed let's make on ramdisk /dev/shm/random-c/
    char *t;
    FILE *F;

    int num_char=10;
    int arg_cnt=1;

    if(argc>0){
        //-- why nobody love C ? one of the reason is these kind parsing thing
        while ((t = /*string.h->*/strtok(argv[0], "=")) != NULL) {
            argv[0] = NULL;
            if(arg_cnt == 2){
                num_char = /*stdlib.h->*/atoi(t);
            }
            arg_cnt++;
        }
    }else{
        //-- get random number betwen 1 to 1000
        num_char = (rand() % 1000)+1;
    }

    init_random();


   //-- create random data
    rnd_out = get_rnd_char(num_char);


    //-- creating "log" path
    //-- why nobody love C ? more reason
   rnd_file = get_rnd_char(20);
   // "/dev/shm/random-c/xxxxxxxxxxxxxxxxxxxx" -> 38 chars + 1 for \0
   rnd_path = (char *)/*stdlib.h->*/malloc((38 * sizeof(char)) + 1);
   rnd_path[0] = '\0';
   /*string.h->*/strcat(rnd_path,"/dev/shm/random-c/");
   /*string.h->*/strcat(rnd_path,rnd_file);

    //-- save to file
    F = /*stdio.h->*/fopen(rnd_path,"w");
        /*stdio.h->*/fprintf(F,"%s",rnd_out);
    /*stdio.h->*/fclose(F);


   //-- send output to browser
   /*gwan.h->*/xbuf_cat(get_reply(argv), rnd_out);


    //-- cleanup memory
    //-- why nobody love C ? MAIN reason: no easy way of memory management
   /*stdlib.h->*/free(rnd_file);
   /*stdlib.h->*/free(rnd_out);
   /*stdlib.h->*/free(rnd_path);

   return 200; // return an HTTP code (200:'OK')
}

// ============================================================================
// End of Source Code
// ============================================================================

在浏览器上运行：
```
http://localhost:8080/?random.c 
```
然后你应该在/ dev / shm / random-c /

这里是'问题'，运行：

ab -n 1000 'http://localhost:8080/?random.c'

我的ubuntu有输出：

Finished 1000 requests


Server Software:        G-WAN
Server Hostname:        localhost
Server Port:            8080

Document Path:          /?random.c
Document Length:        440 bytes

Concurrency Level:      1
Time taken for tests:   0.368 seconds
Complete requests:      1000
Failed requests:        361
   (Connect: 0, Receive: 0, Length: 361, Exceptions: 0)
Write errors:           0
Total transferred:      556492 bytes
HTML transferred:       286575 bytes
Requests per second:    2718.73 [#/sec] (mean)
Time per request:       0.368 [ms] (mean)
Time per request:       0.368 [ms] (mean, across all concurrent requests)
Transfer rate:          1477.49 [Kbytes/sec] received

尝试：

[bash]# ls /dev/shm/random-c/

该目录仅列出4或5个随机文件，预计为1000files

在random.c和perl的版本random.pl

所以回到开始的问题，如何禁用GWAN内部缓存，我尝试阅读gwan用户指南，在处理程序中设置东西，但什么也没找到（或者我错过了该指南中的内容）。

感谢GWAN团队为这个伟大的产品。任何答案欢迎..谢谢

Answer 1

我认为您所谈论的功能是微缓存。要禁用它，URI必须在200 ms内的每个请求上都是唯一的。（比如在URI上添加随机数）

G-WAN FAQ州：

“为了不需要前端缓存服务器（并让G-WAN用作缓存反向代理），G-WAN支持微缓存，一种RESTful功能。当调用给定的URI时在高并发性并且当生成有效载荷需要花费大量时间时，G-WAN将自动缓存页面200毫秒（Internet上的平均延迟）以确保缓存是最新的：在200毫秒内连续请求提供预期结果。为了防止触发微缓存，请为并发请求使用更改的查询参数（每个用户会话ID，随机，计数器等）。“

请注意，对于v4.10 +默认情况下禁用缓存，请查看gwan/init.c文件。

如何禁用G-WAN servlet内部缓存？

1 个答案: