You guys sure about this? vmstat uses stats gathered by the kernel in the structure variable kstat (of type struct kernel_stat). Here follows the func that updates this variable, it seems that time
You guys sure about this? vmstat uses stats gathered by the kernel in the structure variable kstat (of type struct kernel_stat). Here follows the func that updates this variable, it seems that time
Many people helped me to solve the interrupt distribution problem. We tested the throughput of Layer 3 forwarding on a SMP machine which equips two Zero proessor(2Ghz). This is our results: -- SMP |
There is something called 'irq affinity' which may be interesting for you. See here: http://www.dell.com/us/en/esg/topics/power_ps1q02-morse.htm /proc/irq/?/smp_affinity SMP is not always a win. Rega
Hello! Not always good for routing... Were you still get the problem were one interface is the output device from devices bound to different CPU's. TX-ring can hold skb's from many CPU's so a lot of
What was your cpu utilization like in the bound vs split scenarios? Does your e1000 driver have transmit interrupts enabled or disabled? I'd be really interested to see the results with two flows in
Not measured. Gonna take a look w. varient of Manfred's loadtest when possible. But measuring the CPU this way also gives affects throughput. Other softirq's are allowed to run as well now. :-) Over
I ran some tests this afternoon. The setup is: 2 x 1ghz PIII cpus w 256k cache 2 intel 82542 gig-e cards linux 2.4.20-pre11 kernel. I don't have the NAPI e1000 driver. I actually have to ship a 2.4.1
This is approximately what one should expect, correct? If you have only one task (flow), then the float case will be slower than the bound/split case (as long as the CPU isnt the bottleneck), because
NAPI stuff will do interrupt mitigation for you. You probably get a lot less RX interrupts at your loads. I did the old trick to clean TX-buffers at hard_xmit as well but don't see any particularly w
I used perfctr-2.4.0-pre2 to grab the CPU performance counters. I was interested in cache invalidates, etc. I guess I'll try using oprofile to see where in the code I'm really spending the time. Rig