Bandwidth on CoovaChilli Services


#1

Hi, Everybody,
Currently, I'm using a Modem TP-Link Archer C7 and Bandwidth is 150Mbps. After I installed Coovachilli services, the problem is that the bandwidth is limited to only 30-40Mbps.
Help me, Please!


#2

Kind of strange. I use wifidog (similar features as coova), i haven't seen any bandwidth degradation.
Are you measuring over WiFi or lan cable?
Are results consistent across multiple tests?


#3

I try tests over both wifi and lan cable. However, the same results multiple tests. it's only 30-40Mbps.


#4

You always have bandwidth penalty because of chilli using tun interface, which stresses CPU
for transfere of data. There is a kernel module supposed to improve thruput of chilli, but real Black Magic to setup. As chilli is much more sophisticated than wifidog, you might switch, in case you do not need the top features of chilli.


#5

This means that the bandwidth through coovachilli depends on the cpu of the device??


#6

No. coova passes all data from/to (wifi) clients via tun interface. Also, but not only, to throttle download speed, if required. But this passing of data costs CPU cycles. Which limits bandwidth.


#7

Chilli passes all of the client's packets through userspace in order to monitor it and if configured, intentionally limit the bandwidth. That takes CPU power.

Without chilli, the packets go much more directly from the wifi driver to the ethernet driver in the kernel. This has been optimized to be fast.

You can run top while heavy traffic is occurring to see if the chilli process is indeed taking all the CPU.


#8

It means that the bandwidth through coova is sufficient. However, depending on the processor speed of the device?


#9

Currently, Bandwidth is not limited. But when passing through Coovachilli, bandwidth is limited. I think the CPU is not strong enough to handle.


#10

The weak part of the C7 is its single core MIPS processor. It is a good machine within its price class, but really isn't suitable for applications with >100 Mb ISP speeds.


#11

When I keep the C7 at firmware stock with ISP ~ 500Mbps speed through wifi still reach up to 450Mbps. But convert to firmware lede with coova it's only 30-40Mbps. Maybe Coova on lede need hardware stronger.


#12

Maybe Coova on lede need hardware stronger.< When using coova-chilli, independent upon hardware, you always have lower thuput than without using coova.


#13

Ok! I just tried Linksys WRT1900ACS. Bandwidth input and output through coova-chilli. Bandwidth is almost unchanged.
=> The bandwidth through coova-chilli depends a lot on the hardware of the device.


#14

Hi all,

I have been facing the exact same issue. My hardware is using qca9531 chip but when I transfer a large file it downloads at 20-25mbps. and the CPU tops to around 92%... I have even installed the kernel module xt_coova.ko but nothing has changed. in the firewall of LEDE trunk there is an option like "flow_offloading" I enabled to see if it changes anything but nothing so far...
please suggest what could be done? should I change the kernel version to 4.9. will it make a difference?

Thanks!


#15

Coova pulls every packet out of the kernel, inspects it as a user process, then puts it back into the kernel. It's not going to be efficient on CPU usage.