tl; dr：第一个cpu核心始终饱和,所有其他核心始终负载不足.
基于Ubuntu的Xen XCP中的VM：
$uname -a Linux MYHOST 2.6.38-15-virtual #59-Ubuntu SMP Fri Apr 27 16:40:18 UTC 2012 i686 i686 i386 GNU/Linux $lsb_release -a No LSB modules are available. distributor ID: Ubuntu Description: Ubuntu 11.04 Release: 11.04 Codename: natty
该VM有8个cpu内核.
这个VM上运行着10个单线程工作进程,它们通过FCGI接口连接到Nginx服务器(在本地网络端口上侦听).
在来自AB的合成负载下,只有八个的第一个核心被加载到100％(从htop看).它或多或少地保持在非常高的负载下,并且所有其他核心在0到100％的任何地方加载,或多或少地随机加载(并且这些核心的cpu负载正在跳跃).
以下是我在htop中加载时通常看到的内容：
1 [||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||99.3%] Tasks: 70,35 thr; 11 running 2 [||||||||||||||| 15.0%] Load average: 3.86 1.05 0.39 3 [||||||||||||||||||||||||||||||||||| 36.7%] Uptime: 22 days,06:31:57 4 [|||||||||||||||| 15.7%] 5 [||||||||||||||||||||| 22.4%] 6 [||||||||||||||||||| 19.9%] 7 [|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 71.2%] 8 [|||||||||||||||||||||||||||||| 31.3%] Mem[|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||394/4028MB] Swp[ 0/5362MB] PID USER PRI NI VIRT RES SHR S cpu% MEM% TIME+ Command 26213 www-data 20 0 49748 26952 2448 R 29.0 0.7 10:42.61 /usr/bin/luajit2 26227 www-data 20 0 50172 27412 2452 R 27.0 0.7 10:43.53 /usr/bin/luajit2 26221 www-data 20 0 50736 27948 2452 R 27.0 0.7 10:39.02 /usr/bin/luajit2 26234 www-data 20 0 50128 27232 2452 R 27.0 0.7 10:36.36 /usr/bin/luajit2 26218 www-data 20 0 50232 27376 2452 R 26.0 0.7 10:39.32 /usr/bin/luajit2 26214 www-data 20 0 51268 28496 2452 R 26.0 0.7 10:58.15 /usr/bin/luajit2 26232 www-data 20 0 50420 27588 2452 R 25.0 0.7 10:39.21 /usr/bin/luajit2 26217 www-data 20 0 50236 27348 2452 R 25.0 0.7 10:34.44 /usr/bin/luajit2 26219 www-data 20 0 50748 27960 2448 R 23.0 0.7 10:45.30 /usr/bin/luajit2 26239 www-data 20 0 49772 27188 2452 R 22.0 0.7 10:39.39 /usr/bin/luajit2 26368 www-data 20 0 10856 3796 968 S 15.0 0.1 1:12.62 Nginx: worker process 26369 www-data 20 0 10652 3504 968 S 2.0 0.1 1:12.75 Nginx: worker process 26372 www-data 20 0 10520 3504 968 S 0.0 0.1 1:18.64 Nginx: worker process ...
在负载测试期间,所有工作进程都在R中,负载测试运行大约10-15分钟(并且性能大约为700-900次点击/秒).当然,流量是从外部机器生成的.
看起来这个cpu核心负载不平衡是主要的性能瓶颈,如果所有核心均匀加载,性能可能会更高.
有关如何解决此问题的任何线索？
请告诉我是否可以提供更多信息.
看起来cpu0接收到每个eth1中断,并且有很多.
$cat /proc/interrupts
cpu0 cpu1 cpu2 cpu3 cpu4 cpu5 cpu6 cpu7
283: 113720624 0 0 0 0 0 0 0 xen-dyn-event eth1
284: 1 0 0 0 0 0 0 0 xen-dyn-event eth0
285: 2254 0 0 3873799 0 0 0 0 xen-dyn-event blkif
286: 23 0 0 0 0 0 0 0 xen-dyn-event hvc_console
287: 492 42 0 0 0 0 0 295324 xen-dyn-event xenbus
288: 0 0 0 0 0 0 0 222294 xen-percpu-ipi callfuncsingle7
289: 0 0 0 0 0 0 0 0 xen-percpu-virq debug7
290: 0 0 0 0 0 0 0 151302 xen-percpu-ipi callfunc7
291: 0 0 0 0 0 0 0 3236015 xen-percpu-ipi resched7
292: 0 0 0 0 0 0 0 60064 xen-percpu-ipi spinlock7
293: 0 0 0 0 0 0 0 12355510 xen-percpu-virq timer7
294: 0 0 0 0 0 0 803174 0 xen-percpu-ipi callfuncsingle6
295: 0 0 0 0 0 0 0 0 xen-percpu-virq debug6
296: 0 0 0 0 0 0 60027 0 xen-percpu-ipi callfunc6
297: 0 0 0 0 0 0 5374762 0 xen-percpu-ipi resched6
298: 0 0 0 0 0 0 64976 0 xen-percpu-ipi spinlock6
299: 0 0 0 0 0 0 15294870 0 xen-percpu-virq timer6
300: 0 0 0 0 0 264441 0 0 xen-percpu-ipi callfuncsingle5
301: 0 0 0 0 0 0 0 0 xen-percpu-virq debug5
302: 0 0 0 0 0 79324 0 0 xen-percpu-ipi callfunc5
303: 0 0 0 0 0 3468144 0 0 xen-percpu-ipi resched5
304: 0 0 0 0 0 66269 0 0 xen-percpu-ipi spinlock5
305: 0 0 0 0 0 12778464 0 0 xen-percpu-virq timer5
306: 0 0 0 0 844591 0 0 0 xen-percpu-ipi callfuncsingle4
307: 0 0 0 0 0 0 0 0 xen-percpu-virq debug4
308: 0 0 0 0 75293 0 0 0 xen-percpu-ipi callfunc4
309: 0 0 0 0 3482146 0 0 0 xen-percpu-ipi resched4
310: 0 0 0 0 79312 0 0 0 xen-percpu-ipi spinlock4
311: 0 0 0 0 21642424 0 0 0 xen-percpu-virq timer4
312: 0 0 0 449141 0 0 0 0 xen-percpu-ipi callfuncsingle3
313: 0 0 0 0 0 0 0 0 xen-percpu-virq debug3
314: 0 0 0 95405 0 0 0 0 xen-percpu-ipi callfunc3
315: 0 0 0 3802992 0 0 0 0 xen-percpu-ipi resched3
316: 0 0 0 76607 0 0 0 0 xen-percpu-ipi spinlock3
317: 0 0 0 16439729 0 0 0 0 xen-percpu-virq timer3
318: 0 0 876383 0 0 0 0 0 xen-percpu-ipi callfuncsingle2
319: 0 0 0 0 0 0 0 0 xen-percpu-virq debug2
320: 0 0 76416 0 0 0 0 0 xen-percpu-ipi callfunc2
321: 0 0 3422476 0 0 0 0 0 xen-percpu-ipi resched2
322: 0 0 69217 0 0 0 0 0 xen-percpu-ipi spinlock2
323: 0 0 10247182 0 0 0 0 0 xen-percpu-virq timer2
324: 0 393514 0 0 0 0 0 0 xen-percpu-ipi callfuncsingle1
325: 0 0 0 0 0 0 0 0 xen-percpu-virq debug1
326: 0 95773 0 0 0 0 0 0 xen-percpu-ipi callfunc1
327: 0 3551629 0 0 0 0 0 0 xen-percpu-ipi resched1
328: 0 77823 0 0 0 0 0 0 xen-percpu-ipi spinlock1
329: 0 13784021 0 0 0 0 0 0 xen-percpu-virq timer1
330: 730435 0 0 0 0 0 0 0 xen-percpu-ipi callfuncsingle0
331: 0 0 0 0 0 0 0 0 xen-percpu-virq debug0
332: 39649 0 0 0 0 0 0 0 xen-percpu-ipi callfunc0
333: 3607120 0 0 0 0 0 0 0 xen-percpu-ipi resched0
334: 348740 0 0 0 0 0 0 0 xen-percpu-ipi spinlock0
335: 89912004 0 0 0 0 0 0 0 xen-percpu-virq timer0
NMI: 0 0 0 0 0 0 0 0 Non-maskable interrupts
LOC: 0 0 0 0 0 0 0 0 Local timer interrupts
SPU: 0 0 0 0 0 0 0 0 SpurIoUs interrupts
PMI: 0 0 0 0 0 0 0 0 Performance monitoring interrupts
IWI: 0 0 0 0 0 0 0 0 IRQ work interrupts
RES: 3607120 3551629 3422476 3802992 3482146 3468144 5374762 3236015 Rescheduling interrupts
CAL: 770084 489287 952799 544546 919884 343765 863201 373596 Function call interrupts
TLB: 0 0 0 0 0 0 0 0 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
MCE: 0 0 0 0 0 0 0 0 Machine check exceptions
MCP: 0 0 0 0 0 0 0 0 Machine check polls
ERR: 0
MIS: 0
