我使用 Linux 系统作为路由器/防火墙，其内核如下：
Linux gentoo 6.0.8-gentoo-stripped-wireless #1 SMP PREEMPT_DYNAMIC Tue Nov 15 08:54:22 CST 2022 x86_64 AMD FX(tm)-8150 Eight-Core Processor AuthenticAMD GNU/Linux
如果需要，我可以提供 .config。
我正在使用以下 NIC：
0b:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)
Settings for lan:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Link partner advertised pause frame use: Symmetric
Link partner advertised auto-negotiation: Yes
Link partner advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Auto-negotiation: on
master-slave cfg: preferred slave
master-slave status: slave
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: d
Link detected: yes
06:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
Settings for wan:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Auto-negotiation: on
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
MDI-X: off (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes
我能够运行 iperf3 并获得一致的高质量结果：
-----------------------------------------------------------
Server listening on 5201 (test #1)
-----------------------------------------------------------
Accepted connection from 10.10.10.5, port 49356
[ 5] local 10.10.10.1 port 5201 connected to 10.10.10.5 port 49358
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 110 MBytes 919 Mbits/sec
[ 5] 1.00-2.00 sec 112 MBytes 941 Mbits/sec
[ 5] 2.00-3.00 sec 112 MBytes 941 Mbits/sec
[ 5] 3.00-4.00 sec 111 MBytes 931 Mbits/sec
[ 5] 4.00-5.00 sec 112 MBytes 941 Mbits/sec
[ 5] 5.00-6.00 sec 112 MBytes 941 Mbits/sec
[ 5] 6.00-7.00 sec 111 MBytes 928 Mbits/sec
[ 5] 7.00-8.00 sec 112 MBytes 941 Mbits/sec
[ 5] 8.00-9.00 sec 112 MBytes 941 Mbits/sec
[ 5] 9.00-10.00 sec 111 MBytes 930 Mbits/sec
[ 5] 10.00-10.03 sec 3.08 MBytes 941 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate
[ 5] 0.00-10.03 sec 1.09 GBytes 936 Mbits/sec receiver
-----------------------------------------------------------
但速度测试结果的峰值约为 700mbps，并且水平要低得多：
Retrieving speedtest.net configuration...
Testing from Spectrum (xx)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by xx (xx) [367.09 km]: 29.198 ms
Testing download speed................................................................................
Download: 305.14 Mbit/s
Testing upload speed......................................................................................................
Upload: 38.66 Mbit/s
我购买了 950/40，如果直接连接到调制解调器，就可以从我的台式机上获得该速度。使用 Raspberry Pi 4 作为路由器时，我遇到了性能问题，因为它处于省电模式，当带宽较高时，第一个 CPU 核心会被加载。我从未见过这个东西占用太多 CPU，所以我不认为这里会发生这种情况。我只是不知道为什么我可以直接在路由器/服务器上获得如此快的速度，从我的电脑到互联网，但不能从我的路由器/服务器到互联网或通过互联网获得如此快的速度。我可以调整什么来提高网络性能吗？我想不出是什么让它变慢了。
额外信息：
sysctl.conf：
net.ipv4.ip_forward = 1
net.core.rmem_max = 16777216
net.core.wmem_max = 4194304
net.ipv4.tcp_rmem = 65535 131072 4194304
net.ipv4.tcp_wmem = 65535 131072 194304
我能够通过传输获得非常接近千兆位的速度，也许这是一个单流问题？我不确定。
我搬家了，插上所有东西，现在能获得千兆位。无法解释，但一位频谱工作人员拿着他们的手持式测速仪过来告诉我一定是我的设置导致了问题，我想事实并非如此，特定的电缆插孔/连接存在一些问题？我确保接触良好。真的想不出这该如何解释。