Linux
使用速率控製網路時的高軟中斷
我本來打算在 ServerFault 中發布這個，但我認為這可能是一個更好的地方。如果您認為有更好的地方可以發布此問題，請告訴我。
我有一個使用者空間應用程序，它通過 Java NIO 的 API（又名
epollLinux）執行網路連接。出於展示和診斷目的，我有一個線路測試實用程序。它與iperf.有關環境和測試如何執行的一些資訊。
- Ubuntu 16.04 Desktop 今天更新（4.4.0-34-generic）
- irqbalance 關閉
- Intel X504T1 10GbE (ixgbe) 接收器 <-> Solarflare 10GbE (sfc) 發送器
- 使用 10, 000 個 TCP 套接字
- 套接字使用作業系統預設配置
- 使用者空間讀取緩衝區為 32KB
- 讀數不超過 40hz
線路測試由一個客戶端組成，該客戶端通過 TCP 套接字傳輸盡可能多的資訊。
- 每個套接字的每個 read() 都可以被多次呼叫以獲得高達 98KB/hz（32KB 緩衝區必須被讀取 3 次才能達到上限）
- 這意味著在 40hz 和 98KB 的上限下，每個連接每秒最多可以呼叫 120 次 read()；共閱讀3篇，840KB。
- Line tester 顯示 read() 每秒總共被呼叫了大約 110, 000 次。
線路測試將使用大約 8% 輕鬆使 10GbE 適配器完全飽和
softirqtop - 22:04:29 up 51 min, 1 user, load average: 1.31, 1.02, 0.66 Tasks: 258 total, 1 running, 257 sleeping, 0 stopped, 0 zombie %Cpu(s): 2.2 us, 3.6 sy, 0.0 ni, 85.6 id, 1.1 wa, 0.0 hi, 7.4 si, 0.0 st KiB Mem : 16378912 total, 12909832 free, 2383088 used, 1085992 buff/cache KiB Swap: 16721916 total, 16721916 free, 0 used. 13746736 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 4922 jon 20 0 1553556 492552 127160 S 125.0 3.0 0:54.61 firefox 5099 jon 20 0 7212040 218396 16872 S 75.0 1.3 2:59.88 java 3194 root 20 0 722144 163812 134052 S 18.8 1.0 1:25.63 Xorg 4149 jon 20 0 1588648 147848 75344 S 6.2 0.9 0:28.63 compiz 4197 jon 20 0 544660 40600 26804 S 6.2 0.2 0:01.20 indicator-+ 5186 jon 20 0 41948 3696 3084 R 6.2 0.0 0:00.01 top 1 root 20 0 119744 5884 3964 S 0.0 0.0 0:00.84 systemd 2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd 3 root 20 0 0 0 0 S 0.0 0.0 5:01.01 ksoftirqd/0 5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+ 7 root 20 0 0 0 0 S 0.0 0.0 0:01.06 rcu_sched 8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh 9 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0 10 root rt 0 0 0 0 S 0.0 0.0 0:00.04 watchdog/0 11 root rt 0 0 0 0 S 0.0 0.0 0:00.01 watchdog/1 12 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/1 13 root 20 0 0 0 0 S 0.0 0.0 0:08.16 ksoftirqd/1 cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 0: 17 0 0 0 0 0 0 0 IR-IO-APIC 2-edge timer 1: 0 1 0 0 1 0 0 0 IR-IO-APIC 1-edge i8042 5: 0 0 0 0 0 0 0 0 IR-IO-APIC 5-edge parport0 8: 0 0 0 0 0 1 0 0 IR-IO-APIC 8-edge rtc0 9: 0 0 0 0 0 0 0 0 IR-IO-APIC 9-fasteoi acpi 12: 2 0 1 0 1 0 0 0 IR-IO-APIC 12-edge i8042 16: 50 6 2 6 10 0 0 3 IR-IO-APIC 16-fasteoi ehci_hcd:usb1 17: 1138 35 14 24 227 25 35 24 IR-IO-APIC 17-fasteoi snd_hda_intel 19: 0 1 0 0 0 1 0 0 IR-IO-APIC 19-fasteoi firewire_ohci 23: 11 4 10 1 7 0 0 0 IR-IO-APIC 23-fasteoi ehci_hcd:usb2 24: 0 0 0 0 0 0 0 0 DMAR-MSI 0-edge dmar0 27: 4571 1431 1142 812 1286 1442 985 730 IR-PCI-MSI 327680-edge xhci_hcd 28: 26230 3078 1744 1325 6297 2715 1703 1258 IR-PCI-MSI 512000-edge 0000:00:1f.2 29: 754 43 28 30 215 176 129 76 IR-PCI-MSI 2097152-edge eth0-rx-0 30: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2097153-edge eth0-tx-0 31: 0 0 0 0 1 0 0 0 IR-PCI-MSI 2097154-edge eth0 32: 757 64 28 33 205 169 129 66 IR-PCI-MSI 2621440-edge eth1-rx-0 33: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2621441-edge eth1-tx-0 34: 1 0 0 0 0 0 0 0 IR-PCI-MSI 2621442-edge eth1 35: 1042128 233608 58916 16705 1612687 1484813 1121118 630363 IR-PCI-MSI 1048576-edge enp2s0-TxRx-0 36: 858271 736510 372134 165262 1704892 1127381 1265752 767377 IR-PCI-MSI 1048577-edge enp2s0-TxRx-1 37: 816359 711664 426719 192686 1475309 1307882 807216 712562 IR-PCI-MSI 1048578-edge enp2s0-TxRx-2 38: 934786 714007 432100 217627 1905295 1622682 1150693 517990 IR-PCI-MSI 1048579-edge enp2s0-TxRx-3 39: 0 0 0 0 14185366 0 0 0 IR-PCI-MSI 1048580-edge enp2s0-TxRx-4 40: 0 0 0 0 0 14332864 0 0 IR-PCI-MSI 1048581-edge enp2s0-TxRx-5 41: 0 0 0 0 0 0 14617282 0 IR-PCI-MSI 1048582-edge enp2s0-TxRx-6 42: 0 0 0 0 0 0 0 14840029 IR-PCI-MSI 1048583-edge enp2s0-TxRx-7 43: 57 88 47 34 77 64 75 58 IR-PCI-MSI 1048584-edge enp2s0 44: 0 0 0 0 0 13 1 1 IR-PCI-MSI 360448-edge mei_me 45: 246 20 30 4 345 132 128 142 IR-PCI-MSI 442368-edge snd_hda_intel 46: 63933 9794 7233 4753 28843 19323 17678 11191 IR-PCI-MSI 524288-edge nvidia NMI: 57 43 35 42 103 98 83 76 Non-maskable interrupts LOC: 300755 258293 257168 289802 373725 262211 218677 196510 Local timer interrupts SPU: 0 0 0 0 0 0 0 0 Spurious interrupts PMI: 57 43 35 42 103 98 83 76 Performance monitoring interrupts IWI: 0 0 0 0 1 0 0 0 IRQ work interrupts RTR: 0 0 0 0 0 0 0 0 APIC ICR read retries RES: 7721466 2192716 1958606 3095012 1106115 1189666 309133 169884 Rescheduling interrupts CAL: 2598 2206 2194 1751 1976 2255 2130 2211 Function call interrupts TLB: 5450 6659 6103 5640 4352 5128 4535 4470 TLB shootdowns TRM: 0 0 0 0 0 0 0 0 Thermal event interrupts THR: 0 0 0 0 0 0 0 0 Threshold APIC interrupts DFR: 0 0 0 0 0 0 0 0 Deferred Error APIC interrupts MCE: 0 0 0 0 0 0 0 0 Machine check exceptions MCP: 11 11 11 11 11 11 11 11 Machine check polls ERR: 0 MIS: 0 PIN: 0 0 0 0 0 0 0 0 Posted-interrupt notification event PIW: 0 0 0 0 0 0 0 0 Posted-interrupt wakeup event現在，讓我們將速率控制應用於套接字讀取器。
- 入站速率控制設置為每個連接 50KB
- 因為我們有 10,000 個連接，所以大約是 500MB/s
- 速率控制將讀取頻率設置為 5hz，低於前面範例中的 40hz。
- 速率控制的頻率未對齊，這意味著並非所有連接都使用相同的起始參考進行滴答，但是它們都由單個時鐘控制。
- 時鐘為 40hz；這意味著有 40 次計劃的速率控制讀取發生的機會。
- 在每個 5hz 速率控制讀取期間，套接字最多只能讀取 10KB。因此，它每秒 5 次從套接字緩衝區中讀取 10KB。
- Line tester 顯示 read() 每秒總共被呼叫了大約 47, 000 次。
跳躍量
softirq從 8% 到 50-65%；中斷數量幾乎是原來的三倍，RES 中斷（每個核心）為 26-58 百萬，而之前為 1-7 百萬。top - 22:31:50 up 1:19, 1 user, load average: 2.30, 2.30, 1.96 Tasks: 259 total, 2 running, 257 sleeping, 0 stopped, 0 zombie %Cpu(s): 3.3 us, 5.5 sy, 0.0 ni, 41.2 id, 0.0 wa, 0.0 hi, 50.0 si, 0.0 st KiB Mem : 16378912 total, 11752520 free, 2189080 used, 2437312 buff/cache KiB Swap: 16721916 total, 16721916 free, 0 used. 12590400 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 3 root 20 0 0 0 0 S 82.1 0.0 26:57.43 ksoftirqd/0 5194 jon 20 0 7212040 233488 16720 S 46.2 1.4 12:08.73 java 28 root 20 0 0 0 0 S 40.2 0.0 9:04.84 ksoftirqd/4 33 root 20 0 0 0 0 S 30.9 0.0 7:26.84 ksoftirqd/5 43 root 20 0 0 0 0 R 21.6 0.0 4:26.41 ksoftirqd/7 38 root 20 0 0 0 0 S 21.3 0.0 5:37.16 ksoftirqd/6 4922 jon 20 0 1533388 475124 127784 S 5.6 2.9 2:41.82 firefox 3194 root 20 0 722448 163872 134052 S 5.3 1.0 2:50.84 Xorg 5154 jon 20 0 589896 83876 53964 S 1.7 0.5 0:26.08 plugin-con+ 13 root 20 0 0 0 0 S 1.3 0.0 0:42.60 ksoftirqd/1 4548 jon 20 0 5492168 634252 43104 S 1.3 3.9 2:18.86 java 4149 jon 20 0 1604016 169732 75348 S 1.0 1.0 0:52.62 compiz 18 root 20 0 0 0 0 S 0.7 0.0 0:35.31 ksoftirqd/2 23 root 20 0 0 0 0 S 0.3 0.0 0:22.65 ksoftirqd/3 cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 0: 17 0 0 0 0 0 0 0 IR-IO-APIC 2-edge timer 1: 0 1 0 0 1 0 0 0 IR-IO-APIC 1-edge i8042 5: 0 0 0 0 0 0 0 0 IR-IO-APIC 5-edge parport0 8: 0 0 0 0 0 1 0 0 IR-IO-APIC 8-edge rtc0 9: 0 0 0 0 0 0 0 0 IR-IO-APIC 9-fasteoi acpi 12: 2 0 1 0 1 0 0 0 IR-IO-APIC 12-edge i8042 16: 50 6 2 6 10 0 0 3 IR-IO-APIC 16-fasteoi ehci_hcd:usb1 17: 1138 35 14 24 227 25 35 24 IR-IO-APIC 17-fasteoi snd_hda_intel 19: 0 1 0 0 0 1 0 0 IR-IO-APIC 19-fasteoi firewire_ohci 23: 11 4 10 1 7 0 0 0 IR-IO-APIC 23-fasteoi ehci_hcd:usb2 24: 0 0 0 0 0 0 0 0 DMAR-MSI 0-edge dmar0 27: 6518 1966 1471 1031 4361 3847 2501 1673 IR-PCI-MSI 327680-edge xhci_hcd 28: 26732 3381 1957 1447 6687 3367 2112 1502 IR-PCI-MSI 512000-edge 0000:00:1f.2 29: 930 184 150 114 283 344 232 142 IR-PCI-MSI 2097152-edge eth0-rx-0 30: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2097153-edge eth0-tx-0 31: 0 0 0 0 1 0 0 0 IR-PCI-MSI 2097154-edge eth0 32: 899 234 138 104 277 348 236 143 IR-PCI-MSI 2621440-edge eth1-rx-0 33: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2621441-edge eth1-tx-0 34: 1 0 0 0 0 0 0 0 IR-PCI-MSI 2621442-edge eth1 35: 1339704 330929 97391 31445 2023348 1859243 1369358 782238 IR-PCI-MSI 1048576-edge enp2s0-TxRx-0 36: 1863223 3328011 1764431 788048 2411300 2677922 2540016 1742062 IR-PCI-MSI 1048577-edge enp2s0-TxRx-1 37: 1911973 3426913 2084294 955668 2216702 2894499 2008907 1723010 IR-PCI-MSI 1048578-edge enp2s0-TxRx-2 38: 2064515 3379490 2155421 1093171 2652077 3162801 2369659 1442568 IR-PCI-MSI 1048579-edge enp2s0-TxRx-3 39: 0 0 0 0 23079493 0 0 0 IR-PCI-MSI 1048580-edge enp2s0-TxRx-4 40: 0 0 0 0 0 23379687 0 0 IR-PCI-MSI 1048581-edge enp2s0-TxRx-5 41: 0 0 0 0 0 0 24721093 0 IR-PCI-MSI 1048582-edge enp2s0-TxRx-6 42: 0 0 0 0 0 0 0 25752073 IR-PCI-MSI 1048583-edge enp2s0-TxRx-7 43: 211 430 277 179 142 219 240 197 IR-PCI-MSI 1048584-edge enp2s0 44: 0 0 0 0 0 13 1 1 IR-PCI-MSI 360448-edge mei_me 45: 246 20 30 4 345 132 128 142 IR-PCI-MSI 442368-edge snd_hda_intel 46: 87961 29805 21965 14718 43334 42053 34617 23830 IR-PCI-MSI 524288-edge nvidia NMI: 218 130 107 105 252 247 225 214 Non-maskable interrupts LOC: 716630 636798 640606 679852 641275 555921 488433 446196 Local timer interrupts SPU: 0 0 0 0 0 0 0 0 Spurious interrupts PMI: 218 130 107 105 252 247 225 214 Performance monitoring interrupts IWI: 0 0 0 0 3 0 0 0 IRQ work interrupts RTR: 0 0 0 0 0 0 0 0 APIC ICR read retries RES: 38554509 4165414 4123561 5839087 2680226 2883656 1297965 812274 Rescheduling interrupts CAL: 3292 2356 2373 2014 2215 2496 2375 2474 Function call interrupts TLB: 10997 21211 21364 22716 11757 23899 28023 27646 TLB shootdowns TRM: 0 0 0 0 0 0 0 0 Thermal event interrupts THR: 0 0 0 0 0 0 0 0 Threshold APIC interrupts DFR: 0 0 0 0 0 0 0 0 Deferred Error APIC interrupts MCE: 0 0 0 0 0 0 0 0 Machine check exceptions MCP: 17 17 17 17 17 17 17 17 Machine check polls ERR: 0 MIS: 0 PIN: 0 0 0 0 0 0 0 0 Posted-interrupt notification event PIW: 0 0 0 0 0 0 0 0 Posted-interrupt wakeup event誰能解釋為什麼會發生這種情況以及如何避免它？
作為參考，這裡是
top使用 Outbound Rate Control @ 500MB/stop - 01:26:15 up 4:13, 1 user, load average: 0.38, 0.31, 1.00 Tasks: 254 total, 1 running, 253 sleeping, 0 stopped, 0 zombie %Cpu(s): 1.7 us, 3.7 sy, 0.0 ni, 93.3 id, 0.1 wa, 0.0 hi, 1.2 si, 0.0 st KiB Mem : 16378912 total, 12912528 free, 2209912 used, 1256472 buff/cache KiB Swap: 16721916 total, 16721916 free, 0 used. 13873312 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6560 jon 20 0 7212040 204656 16836 S 38.9 1.2 0:21.37 java 3194 root 20 0 871176 206844 175404 S 1.0 1.3 12:11.62 Xorg 4149 jon 20 0 1909092 221972 99348 S 0.7 1.4 3:21.75 compiz 4548 jon 20 0 5879804 662312 45948 S 0.7 4.0 6:48.86 java 3940 jon 20 0 350840 13196 5468 S 0.3 0.1 0:20.41 ibus-daemon 4922 jon 20 0 1779380 686992 145824 S 0.3 4.2 20:38.42 firefox 5827 root 20 0 0 0 0 S 0.3 0.0 0:00.64 kworker/4:1 6341 root 20 0 0 0 0 S 0.3 0.0 0:00.93 kworker/1:2 6539 root 20 0 0 0 0 S 0.3 0.0 0:00.31 kworker/0:2 1 root 20 0 185280 5896 3964 S 0.0 0.0 0:01.01 systemd 2 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kthreadd 3 root 20 0 0 0 0 S 0.0 0.0 107:56.20 ksoftirqd/0 5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+附加 2、500 個 TCP 連接並使用速率控制看到內部 TCP 出站數據包速率為 20K pps；跳轉到 5, 000 個 TCP 連接會看到該數字跳轉到 105K pps；跳到 7, 500 TCP 使出站跳到 190K pps（這些只是確認讀取的數據包——或者我假設）**
2：將Solarflare卡放在伺服器端，Intel X540T1放在客戶端；我看到 IRQ 固定使用
ksoftirqd/0100% 並且總數約為一個核心。使用 Solarflare ，每個核心的中斷不超過 10, 000。**si``12.5%``RES以下是使用 Solarflare 卡時的伺服器.. 但僅接收到大約 360-400MB/s 而不是目標 500MB/s
top - 11:07:55 up 16 min, 1 user, load average: 1.49, 1.09, 0.62 Tasks: 259 total, 3 running, 256 sleeping, 0 stopped, 0 zombie %Cpu(s): 1.5 us, 2.5 sy, 0.0 ni, 83.5 id, 0.0 wa, 0.0 hi, 12.5 si, 0.0 st KiB Mem : 16378912 total, 12294300 free, 2356136 used, 1728476 buff/cache KiB Swap: 16721916 total, 16721916 free, 0 used. 13067464 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 3 root 20 0 0 0 0 R 99.7 0.0 5:20.82 ksoftirqd/0 4620 jon 20 0 7212040 246176 16712 S 25.6 1.5 1:24.67 java 3241 root 20 0 716936 161772 133628 R 3.3 1.0 0:15.42 Xorg 4659 jon 20 0 654928 36356 27820 S 1.0 0.2 0:00.63 gnome-term+ 4103 jon 20 0 1567768 141048 75340 S 0.7 0.9 0:06.44 compiz 4542 jon 20 0 5688204 601804 43040 S 0.7 3.7 1:03.91 java 7 root 20 0 0 0 0 S 0.3 0.0 0:00.93 rcu_sched 4538 root 20 0 0 0 0 S 0.3 0.0 0:00.68 kworker/4:2 1 root 20 0 119844 5980 4028 S 0.0 0.0 0:00.84 systemd 2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd 5 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+ 8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh 9 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0 10 root rt 0 0 0 0 S 0.0 0.0 0:00.02 watchdog/0 11 root rt 0 0 0 0 S 0.0 0.0 0:00.00 watchdog/1 12 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/1 13 root 20 0 0 0 0 S 0.0 0.0 0:00.02 ksoftirqd/1 cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 0: 17 0 0 0 0 0 0 0 IR-IO-APIC 2-edge timer 1: 1 0 0 1 0 0 0 0 IR-IO-APIC 1-edge i8042 5: 0 0 0 0 0 0 0 0 IR-IO-APIC 5-edge parport0 8: 0 0 0 0 0 1 0 0 IR-IO-APIC 8-edge rtc0 9: 0 0 0 0 0 0 0 0 IR-IO-APIC 9-fasteoi acpi 12: 1 0 1 0 1 0 1 0 IR-IO-APIC 12-edge i8042 16: 61 2 1 3 7 2 1 0 IR-IO-APIC 16-fasteoi ehci_hcd:usb1 17: 1166 55 10 19 245 45 13 19 IR-IO-APIC 17-fasteoi snd_hda_intel 19: 0 0 0 0 2 0 0 0 IR-IO-APIC 19-fasteoi firewire_ohci 23: 26 1 2 0 1 2 0 1 IR-IO-APIC 23-fasteoi ehci_hcd:usb2 24: 0 0 0 0 0 0 0 0 DMAR-MSI 0-edge dmar0 27: 1723 170 168 126 1603 166 135 47 IR-PCI-MSI 327680-edge xhci_hcd 28: 24980 1714 933 754 7492 1546 1202 936 IR-PCI-MSI 512000-edge 0000:00:1f.2 29: 298 2 1 7 159 4 6 1 IR-PCI-MSI 2097152-edge eth0-rx-0 30: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2097153-edge eth0-tx-0 31: 1 0 0 0 0 0 0 0 IR-PCI-MSI 2097154-edge eth0 32: 16878 5179 2952 3044 18575 7842 3822 3939 IR-PCI-MSI 1048576-edge enp2s0f0-0 33: 16174 4967 2787 2583 19305 7883 3507 3862 IR-PCI-MSI 1048577-edge enp2s0f0-1 34: 16707 5192 2952 2659 18031 8588 3496 4393 IR-PCI-MSI 1048578-edge enp2s0f0-2 35: 17726 5431 2951 2746 17183 8105 3529 4238 IR-PCI-MSI 1048579-edge enp2s0f0-3 36: 6 1 0 3 6 3 0 1 IR-PCI-MSI 1050624-edge enp2s0f1-0 37: 1 1 0 0 0 0 0 0 IR-PCI-MSI 1050625-edge enp2s0f1-1 38: 1 1 0 0 0 0 0 0 IR-PCI-MSI 1050626-edge enp2s0f1-2 39: 1 1 0 0 0 0 0 0 IR-PCI-MSI 1050627-edge enp2s0f1-3 40: 414 12 9 3 0 14 18 8 IR-PCI-MSI 2621440-edge eth1-rx-0 41: 0 0 0 0 0 0 0 0 IR-PCI-MSI 2621441-edge eth1-tx-0 42: 1 0 0 0 0 0 0 0 IR-PCI-MSI 2621442-edge eth1 43: 0 0 0 0 10 0 5 0 IR-PCI-MSI 360448-edge mei_me 44: 95 26 8 33 398 384 51 16 IR-PCI-MSI 442368-edge snd_hda_intel 45: 17400 1413 1135 806 17781 1714 1401 988 IR-PCI-MSI 524288-edge nvidia NMI: 37 3 5 3 2 1 1 1 Non-maskable interrupts LOC: 112894 53399 87350 46718 43552 19663 25436 19705 Local timer interrupts SPU: 0 0 0 0 0 0 0 0 Spurious interrupts PMI: 37 3 5 3 2 1 1 1 Performance monitoring interrupts IWI: 0 0 0 0 0 0 0 0 IRQ work interrupts RTR: 0 0 0 0 0 0 0 0 APIC ICR read retries RES: 1808 7668 9364 1244 4161 2554 9171 954 Rescheduling interrupts CAL: 1900 2028 1497 1984 1862 1931 2118 2004 Function call interrupts TLB: 1991 2539 3176 2985 3176 2458 1612 2087 TLB shootdowns TRM: 0 0 0 0 0 0 0 0 Thermal event interrupts THR: 0 0 0 0 0 0 0 0 Threshold APIC interrupts DFR: 0 0 0 0 0 0 0 0 Deferred Error APIC interrupts MCE: 0 0 0 0 0 0 0 0 Machine check exceptions MCP: 5 5 5 5 5 5 5 5 Machine check polls ERR: 0 MIS: 0 PIN: 0 0 0 0 0 0 0 0 Posted-interrupt notification event PIW: 0 0 0 0 0 0 0 0 Posted-interrupt wakeup event
問題最終是在預設配置的套接字上使用速率控制，導致內部 TCP 緩衝區大小由於讀取時間緩慢而自動調整為越來越大的大小。（預設最大大小為 6MB） 當大小自動增長時，TCP 緊湊程序會開始瘋狂地攪動，從而吞噬所有的軟中斷。解決此問題的方法是在使用速率控制時設置顯式 TCP 緩衝區大小以防止這種異常行為。