Can't find the bottleneck

Hi,
I am trying to send a lot of packets (about 500mbps concurrent) but the packets send at once seems to be limited around 10k. I've set the nf_conntrack_max to 65535 but i cant seem to get over 10k connections. Does anyone have experience about what's limiting the connections? could it be memory? or cpu? or just a kernel setting?

Care to reveal which device you are talking about...

Continuous gigabit level (routed/NATted) traffic requires a powerful CPU, x86_64 style. Or at least mvebu or something like that.

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Hi,
Sorry... forgot to mention! I'm using a WNDR3700 (V2), im thinking about switching over to a x86-64 system but i would think it would handle at least 50k connections.... (like the other NAT modem i had before, which allowed me around 50k connections i think).

For wndr3700v2 the limiting factor will be CPU power. It can survive e.g. speed test with 200Mb speed, but those speeds with 50k simultaneous connections? No way.

If there is any SQM QoS activity, the routing power decreases to some 90Mb total.

50,000 active connections??? That seems completely inconsistent with either GigE or with all-in-one router use. You might want to reconsider what metrics are truly important.

1 Gbps / 50,000 connections = 20 kbps per connection

20 connected users (a reasonable, per-AP limit) * 10 active connections per "heavy" interactive app (browser, for example) * 5 interactive apps = 1,000 active connections