caching - g-wan - 再现性能声明

Question

在Ubuntu 12.04 LTS下使用gwan_linux64-bit.tar.bz2解压运行gwan

然后将 wrk 指向它(使用空文件 null.html)

wrk --timeout 10 -t 2 -c 100 -d20s http://127.0.0.1:8080/null.html
Running 20s test @ http://127.0.0.1:8080/null.html
  2 threads and 100 connections
    Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    11.65s     5.10s   13.89s    83.91%
    Req/Sec     3.33k     3.65k   12.33k    75.19%
  125067 requests in 20.01s, 32.08MB read
  Socket errors: connect 0, read 37, write 0, timeout 49
Requests/sec:   6251.46
Transfer/sec:      1.60MB

.. 性能很差，实际上似乎存在某种巨大的延迟问题。在测试期间，gwan 忙于 200%，而 wrk 忙于 67%。

指向nginx，wrk忙200%，nginx忙45%:

wrk --timeout 10 -t 2 -c 100 -d20s http://127.0.0.1/null.html
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   371.81us  134.05us  24.04ms   91.26%
    Req/Sec    72.75k     7.38k  109.22k    68.21%
  2740883 requests in 20.00s, 540.95MB read
Requests/sec: 137046.70
Transfer/sec:     27.05MB

将 weighttpd 指向 nginx 会得到更快的结果:

/usr/local/bin/weighttp -k -n 2000000 -c 500 -t 3 http://127.0.0.1/null.html
weighttp - a lightweight and simple webserver benchmarking tool

starting benchmark...
spawning thread #1: 167 concurrent requests, 666667 total requests
spawning thread #2: 167 concurrent requests, 666667 total requests
spawning thread #3: 166 concurrent requests, 666666 total requests
progress:   9% done
progress:  19% done
progress:  29% done
progress:  39% done
progress:  49% done
progress:  59% done
progress:  69% done
progress:  79% done
progress:  89% done
progress:  99% done

finished in 7 sec, 13 millisec and 293 microsec, 285172 req/s, 57633 kbyte/s
requests: 2000000 total, 2000000 started, 2000000 done, 2000000 succeeded, 0 failed, 0 errored
status codes: 2000000 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 413901205 bytes total, 413901205 bytes http, 0 bytes data

服务器是一个虚拟的8核专用服务器(裸机)，在KVM下

我从哪里着手确定 gwan 在这个平台上遇到的问题？

我已经在同一操作系统上测试了 lighttpd、nginx 和 node.js，结果都符合预期。服务器已经以通常的方式进行了调整，包括扩展的临时端口、增加的 ulimits、调整的时间等待回收等。

Answer 1

十一月7 更新:我们已经修复了 G-WAN v4.11.7 中的空文件问题，并且 G-WAN 现在在这场比赛中比 Nginx 快两倍(禁用 www 缓存)。

G-WAN 的最新版本比 Nginx 更快，具有小和大文件，默认情况下禁用 G-WAN 缓存，以便人们更容易将 G-WAN 与其他服务器，如 Nginx。

Nginx 有一些缓存功能(跳过 stat() 调用的 fd cahe 和基于 memcached 的模块)但两者都必然比 G-WAN 的本地缓存慢得多。

禁用缓存对于某些应用程序(如 CDN)也是可取的。 AJAX 应用程序等其他应用程序极大地受益于 G-WAN 缓存功能，因此可以随意重新启用缓存，甚至可以根据每个请求重新启用。

希望这能澄清这个问题。

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"reproducing the performance claims"

首先，标题具有误导性，因为上面记录不完整*的测试没有使用相同的工具，也没有使用 G-WAN 测试获取的 HTTP 资源。

[*] 你的 nginx.conf 文件在哪里？两台服务器的 HTTP 响应 header 是什么？您的“裸机” 8 核 CPU 是什么？

G-WAN 测试基于 ab.c ，由 G-WAN 团队为 weighttp 编写的包装器(Lighttpd server Team做的测试工具)因为ab.c泄露的信息是much more informative .

其次，被测试的文件“null.html”是……一个空文件。

我们不会浪费时间讨论此类测试的无关紧要(您的网站正在提供多少空 HTML 文件？)，但这很可能是观察到的原因 “表现不佳”。

G-WAN 不是为空文件服务而创建的(我们从未尝试过也没有人要求这样做)。但我们肯定会添加此功能以避免此类测试造成的困惑。

如果您想“检查声明”，我建议您使用 weighttp(测试中最快的 HTTP 加载工具)和 100。 bin 文件(一个 100 字节的文件，具有不可压缩的 MIME 类型:这里不会涉及 Gzip)。

使用非空文件 Nginx is massively slower than G-WAN ，即使在独立测试中也是如此。

到目前为止，我们还不知道wrk，但它似乎是由Nginx team 制作的工具。 :

“wrk 是专门为尝试将 nginx 推向极限而编写的，并在第一轮测试中被推高至 0.5Mr/s。”

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更新(一天后)

既然你们懒得发布更多数据，我们就这样做了:

                    wrk                  weighttp
           ----------------------- -----------------------
Web Server 0.html RPS 100.html RPS 0.html RPS 100.html RPS
---------- ---------- ------------ ---------- ------------
G-WAN       80,783.03   649,367.11    175,515      717,813
Nginx      198,800.93   179,939.40    184,046      199,075

在您的测试中，我们可以看到 wrk 比 weighttp 稍慢。

我们还可以看到 G-WAN 比使用两种 HTTP 加载工具的 Nginx 更快。

详细结果如下:

---

广域网

./wrk -c300 -d3 -t6 "http://127.0.0.1:8080/0.html"
Running 3s test @ http://127.0.0.1:8080/0.html
  6 threads and 300 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     3.87ms    5.30ms  80.97ms   99.53%
    Req/Sec    14.73k     1.60k   16.33k    94.67%
  248455 requests in 3.08s, 55.68MB read
  Socket errors: connect 0, read 248448, write 0, timeout 0
Requests/sec:  80783.03
Transfer/sec:     18.10MB

./wrk -c300 -d3 -t6 "http://127.0.0.1:8080/100.html"
Running 3s test @ http://127.0.0.1:8080/100.html
  6 threads and 300 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   263.15us  381.82us  16.50ms   99.60%
    Req/Sec   115.55k    14.38k  154.55k    82.70%
  1946700 requests in 3.00s, 655.35MB read
Requests/sec: 649367.11
Transfer/sec:    218.61MB


weighttp -kn300000 -c300 -t6 "http://127.0.0.1:8080/0.html"
  progress: 100% done
finished in 1 sec, 709 millisec and 252 microsec, 175515 req/s, 20159 kbyte/s
requests: 300000 total, 300000 started, 300000 done, 150147 succeeded, 149853 failed, 0 errored
status codes: 150147 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 35284545 bytes total, 35284545 bytes http, 0 bytes data

weighttp -kn300000 -c300 -t6 "http://127.0.0.1:8080/100.html"
  progress: 100% done
finished in 0 sec, 417 millisec and 935 microsec, 717813 req/s, 247449 kbyte/s
requests: 300000 total, 300000 started, 300000 done, 300000 succeeded, 0 failed, 0 errored
status codes: 300000 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 105900000 bytes total, 75900000 bytes http, 30000000 bytes data

---

Nginx

./wrk -c300 -d3 -t6 "http://127.0.0.1:8080/100.html"
Running 3s test @ http://127.0.0.1:8080/100.html
  6 threads and 300 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     1.54ms    1.16ms  11.67ms   72.91%
    Req/Sec    34.47k     6.02k   56.31k    70.65%
  539743 requests in 3.00s, 180.42MB read
Requests/sec: 179939.40
Transfer/sec:     60.15MB

./wrk -c300 -d3 -t6 "http://127.0.0.1:8080/0.html"
Running 3s test @ http://127.0.0.1:8080/0.html
  6 threads and 300 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     1.44ms    1.15ms   9.37ms   75.93%
    Req/Sec    38.16k     8.57k   62.20k    69.98%
  596070 requests in 3.00s, 140.69MB read
Requests/sec: 198800.93
Transfer/sec:     46.92MB


weighttp -kn300000 -c300 -t6 "http://127.0.0.1:8080/0.html"
  progress: 100% done
finished in 1 sec, 630 millisec and 19 microsec, 184046 req/s, 44484 kbyte/s
requests: 300000 total, 300000 started, 300000 done, 300000 succeeded, 0 failed, 0 errored
status codes: 300000 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 74250375 bytes total, 74250375 bytes http, 0 bytes data

weighttp -kn300000 -c300 -t6 "http://127.0.0.1:8080/100.html"
  progress: 100% done
finished in 1 sec, 506 millisec and 968 microsec, 199075 req/s, 68140 kbyte/s
requests: 300000 total, 300000 started, 300000 done, 300000 succeeded, 0 failed, 0 errored
status codes: 300000 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 105150400 bytes total, 75150400 bytes http, 30000000 bytes data

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Nginx 配置文件试图匹配 G-WAN 的行为

# ./configure --without-http_charset_module --without-http_ssi_module 
#  --without-http_userid_module --without-http_rewrite_module 
#  --without-http_limit_zone_module --without-http_limit_req_module

user                 www-data;
worker_processes     6;
worker_rlimit_nofile 500000;
pid                  /var/run/nginx.pid;

events {
    # tried other values up to 100000 without better results
    worker_connections   4096;
    # multi_accept on; seems to be slower
    multi_accept         off;
    use                  epoll;
}

http {
    charset              utf-8; # HTTP "Content-Type:" header
    sendfile             on;
    tcp_nopush           on;
    tcp_nodelay          on;
    keepalive_timeout    10;
    keepalive_requests   10; # 1000+ slows-down nginx  enormously...

    types_hash_max_size  2048;
    include              /usr/local/nginx/conf/mime.types;
    default_type         application/octet-stream;

    gzip                 off; # adjust for your tests
    gzip_min_length      500;

    gzip_vary            on; # HTTP "Vary: Accept-Encoding" header
    gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;

   # cache metadata (file time, size, existence, etc) to prevent syscalls 
   # this does not cache file contents. It should helps in benchmarks where
   # a limited number of files is accessed more often than others (this is
   # our case as we serve one single file fetched repeatedly)
   # THIS IS ACTUALY SLOWING-DOWN THE TEST...
   #
   # open_file_cache           max=1000 inactive=20s;
   # open_file_cache_errors    on;
   # open_file_cache_min_uses  2;
   # open_file_cache_valid     300s;

   server {
      listen               127.0.0.1:8080;

       access_log           off;

       # only log critical errors
      #error_log            /usr/local/nginx/logs/error.log crit;
      error_log             /dev/null crit;

      location / {
                           root     /usr/local/nginx/html;
                           index    index.html;
      }
      location = /nop.gif {
                           empty_gif;
      }
      location /imgs {
                           autoindex on;
      }
   }
}

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欢迎发表评论，尤其是来自 Nginx 专家的评论，以便基于这个完整记录的测试进行讨论。