我对 Linux、FreeBSD 和 NetBSD 之间的 Web 服务器性能差异很感兴趣，因为我听说 NetBSD 和 FreeBSD 具有良好的 TCP/IP 实现。
因此，我在 KVM 上设置了具有相同硬件功能的虚拟机（2 个 CPU、RAM：2G、HDD：16G、NIC：virtio），然后分别为 Nginx 安装必要的软件包。
我只是在 ramdisk 上运行了带有静态主页的简单 Nginx（以防止磁盘 I/O 因素）。
我发现 NetBSD 的性能很差，怀疑是 NetBSD 的基础设置比较保守，于是尝试调优一些系统参数，但是 NetBSD 系统调优的资料很少，虽然我也对比 FreeBSD 调优了一些 sysctl 参数，但还是没有好到哪里去。
是否有任何 NetBSD 调整建议，或者 NetBSD 真的不是一个好的 Web 服务器选择？
以下是我的 apache-benchmark 结果：
ab -r -n 10000 -c 500
Server Software: LINUX nginx/1.9.3
Server Hostname: 10.128.81.63
Server Port: 80
Document Path: /
Document Length: 612 bytes
Concurrency Level: 500
Time taken for tests: 0.823 seconds
Complete requests: 10000
Failed requests: 0
Total transferred: 8440000 bytes
HTML transferred: 6120000 bytes
Requests per second: 12155.16 [#/sec] (mean)
Time per request: 41.135 [ms] (mean)
Transfer rate: 10018.51 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 0 0.5 0 4
Processing: 2 16 78.2 8 817
Waiting: 1 16 78.2 8 817
Total: 6 16 78.4 8 819
------------------------------------------------------------
Server Software: FreeBSD nginx/1.9.3
Server Hostname: 10.128.81.67
Server Port: 80
Document Path: /
Document Length: 612 bytes
Concurrency Level: 500
Time taken for tests: 0.443 seconds
Complete requests: 10000
Failed requests: 0
Total transferred: 8440000 bytes
HTML transferred: 6120000 bytes
Requests per second: 22577.85 [#/sec] (mean)
Time per request: 22.146 [ms] (mean)
Transfer rate: 18609.09 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 0 0.5 0 3
Processing: 3 21 7.7 21 214
Waiting: 3 21 7.7 21 214
Total: 6 22 7.6 22 217
------------------------------------------------------------
Server Software: NetBSD nginx/1.9.3
Server Hostname: 10.128.81.69
Server Port: 80
Document Path: /
Document Length: 612 bytes
Concurrency Level: 500
Time taken for tests: 1.350 seconds
Complete requests: 10000
Failed requests: 373
(Connect: 0, Receive: 144, Length: 85, Exceptions: 144)
Total transferred: 8318464 bytes
HTML transferred: 6031872 bytes
Requests per second: 7410.05 [#/sec] (mean)
Time per request: 67.476 [ms] (mean)
Transfer rate: 6019.56 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 29 166.9 0 1003
Processing: 1 20 13.9 19 224
Waiting: 0 20 13.9 19 224
Total: 4 49 169.3 20 1212
答案1
您正在使用 KVM——请注意，据我所知，在 NetBSD 下，virtio 支持可能仍然相当不均衡。
我认为这解释了 Linux 和 FreeBSD（均支持 virtio）以及 NetBSD 之间的性能差异。